390994691 has 2 divisors, whose sum is σ = 390994692. Its totient is φ = 390994690.

The previous prime is 390994631. The next prime is 390994697. The reversal of 390994691 is 196499093.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 390994691 - 2¹⁸ = 390732547 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (390994697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195497345 + 195497346.

It is an arithmetic number, because the mean of its divisors is an integer number (195497346).

Almost surely, 2^390994691 is an apocalyptic number.

390994691 is a deficient number, since it is larger than the sum of its proper divisors (1).

390994691 is an equidigital number, since it uses as much as digits as its factorization.

390994691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 472392, while the sum is 50.

The square root of 390994691 is about 19773.5856889943. The cubic root of 390994691 is about 731.2349715566.

The spelling of 390994691 in words is "three hundred ninety million, nine hundred ninety-four thousand, six hundred ninety-one".