400031636 has 6 divisors (see below), whose sum is σ = 700055370. Its totient is φ = 200015816.

The previous prime is 400031603. The next prime is 400031659. The reversal of 400031636 is 636130004.

It can be written as a sum of positive squares in only one way, i.e., 392436100 + 7595536 = 19810^2 + 2756^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50003951 + ... + 50003958.

It is an arithmetic number, because the mean of its divisors is an integer number (116675895).

Almost surely, 2^400031636 is an apocalyptic number.

It is an amenable number.

400031636 is a deficient number, since it is larger than the sum of its proper divisors (300023734).

400031636 is a wasteful number, since it uses less digits than its factorization.

400031636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100007913 (or 100007911 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 23.

The square root of 400031636 is about 20000.7908843625. The cubic root of 400031636 is about 736.8257238861.

The spelling of 400031636 in words is "four hundred million, thirty-one thousand, six hundred thirty-six".