407890391 has 2 divisors, whose sum is σ = 407890392. Its totient is φ = 407890390.

The previous prime is 407890387. The next prime is 407890397. The reversal of 407890391 is 193098704.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 407890391 - 2² = 407890387 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (407890397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203945195 + 203945196.

It is an arithmetic number, because the mean of its divisors is an integer number (203945196).

Almost surely, 2^407890391 is an apocalyptic number.

407890391 is a deficient number, since it is larger than the sum of its proper divisors (1).

407890391 is an equidigital number, since it uses as much as digits as its factorization.

407890391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 407890391 is about 20196.2964674219. The cubic root of 407890391 is about 741.6195300487.

The spelling of 407890391 in words is "four hundred seven million, eight hundred ninety thousand, three hundred ninety-one".