400776644 has 24 divisors (see below), whose sum is σ = 708364440. Its totient is φ = 198397184.

The previous prime is 400776601. The next prime is 400776667. The reversal of 400776644 is 446677004.

It can be written as a sum of positive squares in 4 ways, for example, as 5244100 + 395532544 = 2290^2 + 19888^2 .

It is a junction number, because it is equal to n+sod(n) for n = 400776598 and 400776607.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 185072 + ... + 187224.

It is an arithmetic number, because the mean of its divisors is an integer number (29515185).

Almost surely, 2^400776644 is an apocalyptic number.

It is an amenable number.

400776644 is a deficient number, since it is larger than the sum of its proper divisors (307587796).

400776644 is a wasteful number, since it uses less digits than its factorization.

400776644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2599 (or 2597 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 38.

The square root of 400776644 is about 20019.4066845149. The cubic root of 400776644 is about 737.2828549261.

The spelling of 400776644 in words is "four hundred million, seven hundred seventy-six thousand, six hundred forty-four".