390812491 has 2 divisors, whose sum is σ = 390812492. Its totient is φ = 390812490.

The previous prime is 390812489. The next prime is 390812551. The reversal of 390812491 is 194218093.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 390812491 - 2¹ = 390812489 is a prime.

Together with 390812489, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 390812491.

It is not a weakly prime, because it can be changed into another prime (390812291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195406245 + 195406246.

It is an arithmetic number, because the mean of its divisors is an integer number (195406246).

Almost surely, 2^390812491 is an apocalyptic number.

390812491 is a deficient number, since it is larger than the sum of its proper divisors (1).

390812491 is an equidigital number, since it uses as much as digits as its factorization.

390812491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 390812491 is about 19768.9779958398. The cubic root of 390812491 is about 731.1213709417.

The spelling of 390812491 in words is "three hundred ninety million, eight hundred twelve thousand, four hundred ninety-one".