42564681 has 12 divisors (see below), whose sum is σ = 61896900. Its totient is φ = 28185120.

The previous prime is 42564659. The next prime is 42564701. The reversal of 42564681 is 18646524.

42564681 is a `hidden beast` number, since 4 + 2 + 5 + 646 + 8 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16646400 + 25918281 = 4080^2 + 5091^2 .

It is not a de Polignac number, because 42564681 - 2⁹ = 42564169 is a prime.

It is a super-2 number, since 2×42564681² = 3623504137263522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (42564611) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14530 + ... + 17211.

It is an arithmetic number, because the mean of its divisors is an integer number (5158075).

Almost surely, 2^42564681 is an apocalyptic number.

It is an amenable number.

42564681 is a deficient number, since it is larger than the sum of its proper divisors (19332219).

42564681 is a wasteful number, since it uses less digits than its factorization.

42564681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31896 (or 31893 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 42564681 is about 6524.1613254119. The cubic root of 42564681 is about 349.1535491250.

The spelling of 42564681 in words is "forty-two million, five hundred sixty-four thousand, six hundred eighty-one".