400400031 has 16 divisors (see below), whose sum is σ = 589849344. Its totient is φ = 240307584.

The previous prime is 400399949. The next prime is 400400041. The reversal of 400400031 is 130004004.

It is not a de Polignac number, because 400400031 - 2²³ = 392011423 is a prime.

It is a super-2 number, since 2×400400031² = 320640369649601922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400400041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 169501 + ... + 171846.

It is an arithmetic number, because the mean of its divisors is an integer number (36865584).

Almost surely, 2^400400031 is an apocalyptic number.

400400031 is a deficient number, since it is larger than the sum of its proper divisors (189449313).

400400031 is a wasteful number, since it uses less digits than its factorization.

400400031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341390.

The product of its (nonzero) digits is 48, while the sum is 12.

The square root of 400400031 is about 20009.9982758620. The cubic root of 400400031 is about 737.0518390276.

Adding to 400400031 its reverse (130004004), we get a palindrome (530404035).

The spelling of 400400031 in words is "four hundred million, four hundred thousand, thirty-one".