390994631 has 2 divisors, whose sum is σ = 390994632. Its totient is φ = 390994630.

The previous prime is 390994607. The next prime is 390994691. The reversal of 390994631 is 136499093.

It is a weak prime.

It is an emirp because it is prime and its reverse (136499093) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-390994631 is a prime.

It is a super-2 number, since 2×390994631² = 305753602941652322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (390994601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195497315 + 195497316.

It is an arithmetic number, because the mean of its divisors is an integer number (195497316).

Almost surely, 2^390994631 is an apocalyptic number.

390994631 is a deficient number, since it is larger than the sum of its proper divisors (1).

390994631 is an equidigital number, since it uses as much as digits as its factorization.

390994631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 157464, while the sum is 44.

The square root of 390994631 is about 19773.5841718187. The cubic root of 390994631 is about 731.2349341528.

The spelling of 390994631 in words is "three hundred ninety million, nine hundred ninety-four thousand, six hundred thirty-one".