388665856 has 20 divisors (see below), whose sum is σ = 776573622. Its totient is φ = 194332672.

The previous prime is 388665833. The next prime is 388665929. The reversal of 388665856 is 658566883.

It can be written as a sum of positive squares in only one way, i.e., 337971456 + 50694400 = 18384^2 + 7120^2 .

It is a super-2 number, since 2×388665856² = 302122295240425472, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 388665797 and 388665806.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 379045 + ... + 380068.

Almost surely, 2^388665856 is an apocalyptic number.

It is an amenable number.

388665856 is a deficient number, since it is larger than the sum of its proper divisors (387907766).

388665856 is an frugal number, since it uses more digits than its factorization.

388665856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 759131 (or 759115 counting only the distinct ones).

The product of its digits is 8294400, while the sum is 55.

The square root of 388665856 is about 19714.6102167910. The cubic root of 388665856 is about 729.7802904199.

The spelling of 388665856 in words is "three hundred eighty-eight million, six hundred sixty-five thousand, eight hundred fifty-six".