646190939 has 8 divisors (see below), whose sum is σ = 675075072. Its totient is φ = 617809320.

The previous prime is 646190933. The next prime is 646190953. The reversal of 646190939 is 939091646.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 646190939 - 2²⁰ = 645142363 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646190893 and 646190902.

It is not an unprimeable number, because it can be changed into a prime (646190933) 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, 122999 + ... + 128144.

It is an arithmetic number, because the mean of its divisors is an integer number (84384384).

Almost surely, 2^646190939 is an apocalyptic number.

646190939 is a deficient number, since it is larger than the sum of its proper divisors (28884133).

646190939 is a wasteful number, since it uses less digits than its factorization.

646190939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251257.

The product of its (nonzero) digits is 314928, while the sum is 47.

The square root of 646190939 is about 25420.2859740012. The cubic root of 646190939 is about 864.5437084705.

The spelling of 646190939 in words is "six hundred forty-six million, one hundred ninety thousand, nine hundred thirty-nine".