642310820 has 12 divisors (see below), whose sum is σ = 1348852764. Its totient is φ = 256924320.

The previous prime is 642310783. The next prime is 642310829. The reversal of 642310820 is 28013246.

It can be written as a sum of positive squares in 2 ways, for example, as 302203456 + 340107364 = 17384^2 + 18442^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 642310820.

It is not an unprimeable number, because it can be changed into a prime (642310829) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16057751 + ... + 16057790.

It is an arithmetic number, because the mean of its divisors is an integer number (112404397).

Almost surely, 2^642310820 is an apocalyptic number.

It is an amenable number.

642310820 is an abundant number, since it is smaller than the sum of its proper divisors (706541944).

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

642310820 is a wasteful number, since it uses less digits than its factorization.

642310820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32115550 (or 32115548 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 642310820 is about 25343.8517198945. The cubic root of 642310820 is about 862.8098199427.

The spelling of 642310820 in words is "six hundred forty-two million, three hundred ten thousand, eight hundred twenty".