642556170 has 24 divisors (see below), whose sum is σ = 1670646276. Its totient is φ = 171348288.

The previous prime is 642556151. The next prime is 642556241. The reversal of 642556170 is 71655246.

It is a happy number.

642556170 is a `hidden beast` number, since 6 + 4 + 25 + 561 + 70 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 634888809 + 7667361 = 25197^2 + 2769^2 .

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 11 ways as a sum of consecutive naturals, for example, 3569667 + ... + 3569846.

Almost surely, 2^642556170 is an apocalyptic number.

642556170 is an abundant number, since it is smaller than the sum of its proper divisors (1028090106).

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

642556170 is a wasteful number, since it uses less digits than its factorization.

642556170 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7139526 (or 7139523 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 36.

The square root of 642556170 is about 25348.6916822151. The cubic root of 642556170 is about 862.9196647067.

The spelling of 642556170 in words is "six hundred forty-two million, five hundred fifty-six thousand, one hundred seventy".