642810620 has 24 divisors (see below), whose sum is σ = 1386387744. Its totient is φ = 250174656.

The previous prime is 642810617. The next prime is 642810631. The reversal of 642810620 is 26018246.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 433592 + ... + 435071.

It is an arithmetic number, because the mean of its divisors is an integer number (57766156).

Almost surely, 2^642810620 is an apocalyptic number.

It is an amenable number.

642810620 is an abundant number, since it is smaller than the sum of its proper divisors (743577124).

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

642810620 is a wasteful number, since it uses less digits than its factorization.

642810620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 868709 (or 868707 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 642810620 is about 25353.7101821410. The cubic root of 642810620 is about 863.0335540662.

Adding to 642810620 its reverse (26018246), we get a palindrome (668828866).

The spelling of 642810620 in words is "six hundred forty-two million, eight hundred ten thousand, six hundred twenty".