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BaseRepresentation
bin10001011100010010
310122000000
4101130102
54241232
61310430
7415200
oct213422
9118000
1071442
1149748
1235416
1326697
141c070
151627c
hex11712

71442 has 42 divisors (see below), whose sum is σ = 186903. Its totient is φ = 20412.

The previous prime is 71437. The next prime is 71443. The reversal of 71442 is 24417.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 35721 + 35721 = 189^2 + 189^2 .

It is a tau number, because it is divible by the number of its divisors (42).

It is an ABA number since it can be written as A⋅BA, here for A=2, B=189.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 71442.

It is not an unprimeable number, because it can be changed into a prime (71443) by changing a digit.

71442 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 10203 + ... + 10209.

271442 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71442

71442 is an abundant number, since it is smaller than the sum of its proper divisors (115461).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71442 is an equidigital number, since it uses as much as digits as its factorization.

71442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34 (or 12 counting only the distinct ones).

The product of its digits is 224, while the sum is 18.

The square root of 71442 is about 267.2863632885. The cubic root of 71442 is about 41.4939266285.

Multiplying 71442 by its sum of digits (18), we get a square (1285956 = 11342).

71442 divided by its sum of digits (18) gives a square (3969 = 632).

Multiplying 71442 by its product of digits (224), we get a cube (16003008 = 2523).

Adding to 71442 its reverse (24417), we get a palindrome (95859).

The spelling of 71442 in words is "seventy-one thousand, four hundred forty-two", and thus it is an iban number.