399545993 has 12 divisors (see below), whose sum is σ = 501910080. Its totient is φ = 311333880.

The previous prime is 399545989. The next prime is 399545999.

399545993 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 399545993 - 2² = 399545989 is a prime.

It is not an unprimeable number, because it can be changed into a prime (399545999) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 235013 + ... + 236706.

It is an arithmetic number, because the mean of its divisors is an integer number (41825840).

Almost surely, 2^399545993 is an apocalyptic number.

It is an amenable number.

399545993 is a deficient number, since it is larger than the sum of its proper divisors (102364087).

399545993 is a wasteful number, since it uses less digits than its factorization.

399545993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471748 (or 471737 counting only the distinct ones).

The product of its digits is 5904900, while the sum is 56.

The square root of 399545993 is about 19988.6466025091. The cubic root of 399545993 is about 736.5274315132.

The spelling of 399545993 in words is "three hundred ninety-nine million, five hundred forty-five thousand, nine hundred ninety-three".