642895208 has 16 divisors (see below), whose sum is σ = 1205698560. Its totient is φ = 321375600.

The previous prime is 642895177. The next prime is 642895223. The reversal of 642895208 is 802598246.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60623 + ... + 70433.

It is an arithmetic number, because the mean of its divisors is an integer number (75356160).

Almost surely, 2^642895208 is an apocalyptic number.

It is an amenable number.

642895208 is a deficient number, since it is larger than the sum of its proper divisors (562803352).

642895208 is a wasteful number, since it uses less digits than its factorization.

642895208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18008 (or 18004 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 44.

The square root of 642895208 is about 25355.3782854841. The cubic root of 642895208 is about 863.0714081807.

The spelling of 642895208 in words is "six hundred forty-two million, eight hundred ninety-five thousand, two hundred eight".