646520838 has 16 divisors (see below), whose sum is σ = 1337629680. Its totient is φ = 208075616.

The previous prime is 646520807. The next prime is 646520839. The reversal of 646520838 is 838025646.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 646520838.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646520839) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1857645 + ... + 1857992.

It is an arithmetic number, because the mean of its divisors is an integer number (83601855).

Almost surely, 2^646520838 is an apocalyptic number.

646520838 is an abundant number, since it is smaller than the sum of its proper divisors (691108842).

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

646520838 is a wasteful number, since it uses less digits than its factorization.

646520838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3715671.

The product of its (nonzero) digits is 276480, while the sum is 42.

The square root of 646520838 is about 25426.7740384029. The cubic root of 646520838 is about 864.6908082233.

The spelling of 646520838 in words is "six hundred forty-six million, five hundred twenty thousand, eight hundred thirty-eight".