642877868 has 24 divisors (see below), whose sum is σ = 1159594800. Its totient is φ = 311662080.

The previous prime is 642877867. The next prime is 642877871. The reversal of 642877868 is 868778246.

It is not an unprimeable number, because it can be changed into a prime (642877867) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 14708 + ... + 38756.

It is an arithmetic number, because the mean of its divisors is an integer number (48316450).

Almost surely, 2^642877868 is an apocalyptic number.

It is an amenable number.

642877868 is a deficient number, since it is larger than the sum of its proper divisors (516716932).

642877868 is a wasteful number, since it uses less digits than its factorization.

642877868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24257 (or 24255 counting only the distinct ones).

The product of its digits is 7225344, while the sum is 56.

The square root of 642877868 is about 25355.0363438903. The cubic root of 642877868 is about 863.0636485995.

The spelling of 642877868 in words is "six hundred forty-two million, eight hundred seventy-seven thousand, eight hundred sixty-eight".