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21472 = 251161
BaseRepresentation
bin101001111100000
31002110021
411033200
51141342
6243224
7116413
oct51740
932407
1021472
1115150
1210514
139a09
147b7a
156567
hex53e0

21472 has 24 divisors (see below), whose sum is σ = 46872. Its totient is φ = 9600.

The previous prime is 21467. The next prime is 21481. The reversal of 21472 is 27412.

Adding to 21472 its reverse (27412), we get a palindrome (48884).

21472 is an esthetic number in base 15, because in such base its adjacent digits differ by 1.

It is a super-2 number, since 2×214722 = 922093568, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable 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 3 ways as a sum of consecutive naturals, for example, 322 + ... + 382.

It is an arithmetic number, because the mean of its divisors is an integer number (1953).

221472 is an apocalyptic number.

21472 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23436).

21472 is an abundant number, since it is smaller than the sum of its proper divisors (25400).

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

21472 is a wasteful number, since it uses less digits than its factorization.

21472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82 (or 74 counting only the distinct ones).

The product of its digits is 112, while the sum is 16.

The square root of 21472 is about 146.5332726721. The cubic root of 21472 is about 27.7944125548.

The spelling of 21472 in words is "twenty-one thousand, four hundred seventy-two", and thus it is an iban number.