399634956 has 72 divisors (see below), whose sum is σ = 1166474400. Its totient is φ = 112997376.

The previous prime is 399634943. The next prime is 399634979. The reversal of 399634956 is 659436993.

399634956 is a `hidden beast` number, since 3 + 99 + 63 + 495 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16270 + ... + 32618.

Almost surely, 2^399634956 is an apocalyptic number.

399634956 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399634956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (583237200).

399634956 is an abundant number, since it is smaller than the sum of its proper divisors (766839444).

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

399634956 is a wasteful number, since it uses less digits than its factorization.

399634956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16463 (or 16458 counting only the distinct ones).

The product of its digits is 4723920, while the sum is 54.

The square root of 399634956 is about 19990.8718169068. The cubic root of 399634956 is about 736.5820925773.

The spelling of 399634956 in words is "three hundred ninety-nine million, six hundred thirty-four thousand, nine hundred fifty-six".