642873634 has 12 divisors (see below), whose sum is σ = 1044194706. Its totient is φ = 296710752.

The previous prime is 642873559. The next prime is 642873641. The reversal of 642873634 is 436378246.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 340218025 + 302655609 = 18445^2 + 17397^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 950659 + ... + 951334.

Almost surely, 2^642873634 is an apocalyptic number.

642873634 is a deficient number, since it is larger than the sum of its proper divisors (401321072).

642873634 is a wasteful number, since it uses less digits than its factorization.

642873634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1902021 (or 1902008 counting only the distinct ones).

The product of its digits is 580608, while the sum is 43.

The square root of 642873634 is about 25354.9528494927. The cubic root of 642873634 is about 863.0617538801.

The spelling of 642873634 in words is "six hundred forty-two million, eight hundred seventy-three thousand, six hundred thirty-four".