401239939 has 2 divisors, whose sum is σ = 401239940. Its totient is φ = 401239938.

The previous prime is 401239931. The next prime is 401240029. The reversal of 401239939 is 939932104.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 401239939 - 2³ = 401239931 is a prime.

It is not a weakly prime, because it can be changed into another prime (401239931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200619969 + 200619970.

It is an arithmetic number, because the mean of its divisors is an integer number (200619970).

Almost surely, 2^401239939 is an apocalyptic number.

401239939 is a deficient number, since it is larger than the sum of its proper divisors (1).

401239939 is an equidigital number, since it uses as much as digits as its factorization.

401239939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 52488, while the sum is 40.

The square root of 401239939 is about 20030.9744895250. The cubic root of 401239939 is about 737.5668434674.

The spelling of 401239939 in words is "four hundred one million, two hundred thirty-nine thousand, nine hundred thirty-nine".