642256170 has 32 divisors (see below), whose sum is σ = 1577264832. Its totient is φ = 167284992.

The previous prime is 642256151. The next prime is 642256187. The reversal of 642256170 is 71652246.

It is an unprimeable number.

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, 247647 + ... + 250226.

It is an arithmetic number, because the mean of its divisors is an integer number (49289526).

Almost surely, 2^642256170 is an apocalyptic number.

642256170 is an abundant number, since it is smaller than the sum of its proper divisors (935008662).

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

642256170 is a wasteful number, since it uses less digits than its factorization.

642256170 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 497926.

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 642256170 is about 25342.7735261948. The cubic root of 642256170 is about 862.7853489792.

The spelling of 642256170 in words is "six hundred forty-two million, two hundred fifty-six thousand, one hundred seventy".