42561072 has 80 divisors (see below), whose sum is σ = 123742080. Its totient is φ = 14004288.

The previous prime is 42561061. The next prime is 42561073. The reversal of 42561072 is 27016524.

42561072 is a `hidden beast` number, since 42 + 5 + 610 + 7 + 2 = 666.

It is a super-2 number, since 2×42561072² = 3622889699578368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (42561073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35263 + ... + 36449.

It is an arithmetic number, because the mean of its divisors is an integer number (1546776).

Almost surely, 2^42561072 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42561072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (61871040).

42561072 is an abundant number, since it is smaller than the sum of its proper divisors (81181008).

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

42561072 is a wasteful number, since it uses less digits than its factorization.

42561072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1287 (or 1275 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 42561072 is about 6523.8847322742. The cubic root of 42561072 is about 349.1436807651.

Adding to 42561072 its reverse (27016524), we get a palindrome (69577596).

The spelling of 42561072 in words is "forty-two million, five hundred sixty-one thousand, seventy-two".