42556840 has 16 divisors (see below), whose sum is σ = 95752980. Its totient is φ = 17022720.

The previous prime is 42556823. The next prime is 42556841. The reversal of 42556840 is 4865524.

It can be written as a sum of positive squares in 2 ways, for example, as 38862756 + 3694084 = 6234^2 + 1922^2 .

It is a super-2 number, since 2×42556840² = 3622169261571200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 42556796 and 42556805.

It is not an unprimeable number, because it can be changed into a prime (42556841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 531921 + ... + 532000.

Almost surely, 2^42556840 is an apocalyptic number.

42556840 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42556840 is an abundant number, since it is smaller than the sum of its proper divisors (53196140).

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

42556840 is a wasteful number, since it uses less digits than its factorization.

42556840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1063932 (or 1063928 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 34.

The square root of 42556840 is about 6523.5603775852. The cubic root of 42556840 is about 349.1321081788.

The spelling of 42556840 in words is "forty-two million, five hundred fifty-six thousand, eight hundred forty".