399640396 has 12 divisors (see below), whose sum is σ = 700329952. Its totient is φ = 199546128.

The previous prime is 399640393. The next prime is 399640411. The reversal of 399640396 is 693046993.

It is a super-2 number, since 2×399640396² = 319424892230073632, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (399640393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65220 + ... + 71083.

Almost surely, 2^399640396 is an apocalyptic number.

It is an amenable number.

399640396 is a deficient number, since it is larger than the sum of its proper divisors (300689556).

399640396 is a wasteful number, since it uses less digits than its factorization.

399640396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137040 (or 137038 counting only the distinct ones).

The product of its (nonzero) digits is 944784, while the sum is 49.

The square root of 399640396 is about 19991.0078785438. The cubic root of 399640396 is about 736.5854347844.

The spelling of 399640396 in words is "three hundred ninety-nine million, six hundred forty thousand, three hundred ninety-six".