642860928 has 64 divisors (see below), whose sum is σ = 1897342800. Its totient is φ = 214285824.

The previous prime is 642860917. The next prime is 642860929. The reversal of 642860928 is 829068246.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642860929) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 89551 + ... + 96462.

Almost surely, 2^642860928 is an apocalyptic number.

It is an amenable number.

642860928 is an abundant number, since it is smaller than the sum of its proper divisors (1254481872).

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

642860928 is a wasteful number, since it uses less digits than its factorization.

642860928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186036 (or 186018 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The square root of 642860928 is about 25354.7022857694. The cubic root of 642860928 is about 863.0560678819.

The spelling of 642860928 in words is "six hundred forty-two million, eight hundred sixty thousand, nine hundred twenty-eight".