642956015 has 16 divisors (see below), whose sum is σ = 831448800. Its totient is φ = 474483072.

The previous prime is 642956003. The next prime is 642956021. The reversal of 642956015 is 510659246.

It is a cyclic number.

It is not a de Polignac number, because 642956015 - 2¹² = 642951919 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 642956015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 149921 + ... + 154149.

It is an arithmetic number, because the mean of its divisors is an integer number (51965550).

Almost surely, 2^642956015 is an apocalyptic number.

642956015 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

642956015 is a deficient number, since it is larger than the sum of its proper divisors (188492785).

642956015 is a wasteful number, since it uses less digits than its factorization.

642956015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6586.

The product of its (nonzero) digits is 64800, while the sum is 38.

The square root of 642956015 is about 25356.5773518431. The cubic root of 642956015 is about 863.0986179696.

The spelling of 642956015 in words is "six hundred forty-two million, nine hundred fifty-six thousand, fifteen".