400398439844 has 24 divisors (see below), whose sum is σ = 754633184760. Its totient is φ = 184790433024.

The previous prime is 400398439841. The next prime is 400398439853. The reversal of 400398439844 is 448934893004.

It can be written as a sum of positive squares in 4 ways, for example, as 4807758244 + 395590681600 = 69338^2 + 628960^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 400398439844.

It is not an unprimeable number, because it can be changed into a prime (400398439841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 982712 + ... + 1329104.

It is an arithmetic number, because the mean of its divisors is an integer number (31443049365).

Almost surely, 2^400398439844 is an apocalyptic number.

It is an amenable number.

400398439844 is a deficient number, since it is larger than the sum of its proper divisors (354234744916).

400398439844 is a wasteful number, since it uses less digits than its factorization.

400398439844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368639 (or 368637 counting only the distinct ones).

The product of its (nonzero) digits is 11943936, while the sum is 56.

The spelling of 400398439844 in words is "four hundred billion, three hundred ninety-eight million, four hundred thirty-nine thousand, eight hundred forty-four".