42402634561 has 27 divisors (see below), whose sum is σ = 51603691041. Its totient is φ = 34737711624.

The previous prime is 42402634553. The next prime is 42402634567. The reversal of 42402634561 is 16543620424.

The square root of 42402634561 is 205919.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 42402634561 - 2³ = 42402634553 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42402634561.

It is not an unprimeable number, because it can be changed into a prime (42402634567) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 33152320 + ... + 33153598.

Almost surely, 2^42402634561 is an apocalyptic number.

42402634561 is the 205919-th square number.

42402634561 is the 102960-th centered octagonal number.

It is an amenable number.

42402634561 is a deficient number, since it is larger than the sum of its proper divisors (9201056480).

42402634561 is an frugal number, since it uses more digits than its factorization.

42402634561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2618 (or 1309 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 37.

The spelling of 42402634561 in words is "forty-two billion, four hundred two million, six hundred thirty-four thousand, five hundred sixty-one".