399425992 has 32 divisors (see below), whose sum is σ = 856627200. Its totient is φ = 171039744.

The previous prime is 399425951. The next prime is 399425993. The reversal of 399425992 is 299524993.

It is a super-2 number, since 2×399425992² = 319082246170368128, which contains 22 as substring.

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (399425993) 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, 90984 + ... + 95272.

It is an arithmetic number, because the mean of its divisors is an integer number (26769600).

Almost surely, 2^399425992 is an apocalyptic number.

It is an amenable number.

399425992 is an abundant number, since it is smaller than the sum of its proper divisors (457201208).

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

399425992 is a wasteful number, since it uses less digits than its factorization.

399425992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5965 (or 5961 counting only the distinct ones).

The product of its digits is 1574640, while the sum is 52.

The square root of 399425992 is about 19985.6446480968. The cubic root of 399425992 is about 736.4536870801.

Subtracting from 399425992 its reverse (299524993), we obtain a palindrome (99900999).

The spelling of 399425992 in words is "three hundred ninety-nine million, four hundred twenty-five thousand, nine hundred ninety-two".