393974965 has 16 divisors (see below), whose sum is σ = 479098800. Its totient is φ = 310976512.

The previous prime is 393974957. The next prime is 393974989. The reversal of 393974965 is 569479393.

It can be written as a sum of positive squares in 8 ways, for example, as 126292644 + 267682321 = 11238^2 + 16361^2 .

It is a cyclic number.

It is not a de Polignac number, because 393974965 - 2³ = 393974957 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 412929 + ... + 413881.

It is an arithmetic number, because the mean of its divisors is an integer number (29943675).

Almost surely, 2^393974965 is an apocalyptic number.

It is an amenable number.

393974965 is a deficient number, since it is larger than the sum of its proper divisors (85123835).

393974965 is an equidigital number, since it uses as much as digits as its factorization.

393974965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1976.

The product of its digits is 5511240, while the sum is 55.

The square root of 393974965 is about 19848.8026087218. The cubic root of 393974965 is about 733.0881654046.

The spelling of 393974965 in words is "three hundred ninety-three million, nine hundred seventy-four thousand, nine hundred sixty-five".