400465565820 has 72 divisors (see below), whose sum is σ = 1267560586656. Its totient is φ = 102147737472.

The previous prime is 400465565809. The next prime is 400465565833. The reversal of 400465565820 is 28565564004.

400465565820 is a `hidden beast` number, since 4 + 0 + 0 + 4 + 6 + 5 + 565 + 82 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 48361267 + ... + 48369546.

It is an arithmetic number, because the mean of its divisors is an integer number (17605008148).

Almost surely, 2^400465565820 is an apocalyptic number.

It is an amenable number.

400465565820 is an abundant number, since it is smaller than the sum of its proper divisors (867095020836).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

400465565820 is a wasteful number, since it uses less digits than its factorization.

400465565820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96730851 (or 96730846 counting only the distinct ones).

The product of its (nonzero) digits is 1152000, while the sum is 45.

The spelling of 400465565820 in words is "four hundred billion, four hundred sixty-five million, five hundred sixty-five thousand, eight hundred twenty".