399730907 has 4 divisors (see below), whose sum is σ = 399771000. Its totient is φ = 399690816.

The previous prime is 399730897. The next prime is 399730913. The reversal of 399730907 is 709037993.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 709037993 = 37 ⋅19163189.

It is a cyclic number.

It is not a de Polignac number, because 399730907 - 2⁸ = 399730651 is a prime.

It is a super-2 number, since 2×399730907² = 319569596022085298, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399730937) 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, 7844 + ... + 29342.

It is an arithmetic number, because the mean of its divisors is an integer number (99942750).

Almost surely, 2^399730907 is an apocalyptic number.

399730907 is a deficient number, since it is larger than the sum of its proper divisors (40093).

399730907 is a wasteful number, since it uses less digits than its factorization.

399730907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40092.

The product of its (nonzero) digits is 321489, while the sum is 47.

The square root of 399730907 is about 19993.2715431967. The cubic root of 399730907 is about 736.6410381489.

The spelling of 399730907 in words is "three hundred ninety-nine million, seven hundred thirty thousand, nine hundred seven".