399606993 has 48 divisors (see below), whose sum is σ = 641592000. Its totient is φ = 245130624.

The previous prime is 399606983. The next prime is 399607003.

399606993 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (399606983) and next prime (399607003).

It is not a de Polignac number, because 399606993 - 2⁶ = 399606929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (399606983) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 702013 + ... + 702581.

It is an arithmetic number, because the mean of its divisors is an integer number (13366500).

Almost surely, 2^399606993 is an apocalyptic number.

It is an amenable number.

399606993 is a deficient number, since it is larger than the sum of its proper divisors (241985007).

399606993 is a wasteful number, since it uses less digits than its factorization.

399606993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 671 (or 628 counting only the distinct ones).

The product of its (nonzero) digits is 2125764, while the sum is 54.

The square root of 399606993 is about 19990.1724104621. The cubic root of 399606993 is about 736.5649122938.

The spelling of 399606993 in words is "three hundred ninety-nine million, six hundred six thousand, nine hundred ninety-three".