390931984 has 15 divisors (see below), whose sum is σ = 757583983. Its totient is φ = 195426448.

The previous prime is 390931969. The next prime is 390931993. The reversal of 390931984 is 489139093.

The square root of 390931984 is 19772.

It is a perfect power (a square), and thus also a powerful number.

It is a super-2 number, since 2×390931984² = 305655632228352512, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 76617 + ... + 81559.

Almost surely, 2^390931984 is an apocalyptic number.

390931984 is the 19772-nd square number.

It is an amenable number.

390931984 is a deficient number, since it is larger than the sum of its proper divisors (366651999).

390931984 is an frugal number, since it uses more digits than its factorization.

390931984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9894 (or 4945 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 46.

The cubic root of 390931984 is about 731.1958780992.

The spelling of 390931984 in words is "three hundred ninety million, nine hundred thirty-one thousand, nine hundred eighty-four".