388995981 has 16 divisors (see below), whose sum is σ = 566499648. Its totient is φ = 235468800.

The previous prime is 388995961. The next prime is 388996009. The reversal of 388995981 is 189599883.

It is not a de Polignac number, because 388995981 - 2¹⁴ = 388979597 is a prime.

It is a super-2 number, since 2×388995981² = 302635746468304722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (388995961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22221 + ... + 35661.

It is an arithmetic number, because the mean of its divisors is an integer number (35406228).

Almost surely, 2^388995981 is an apocalyptic number.

It is an amenable number.

388995981 is a deficient number, since it is larger than the sum of its proper divisors (177503667).

388995981 is a wasteful number, since it uses less digits than its factorization.

388995981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14332.

The product of its digits is 5598720, while the sum is 60.

The square root of 388995981 is about 19722.9810373584. The cubic root of 388995981 is about 729.9868522058.

The spelling of 388995981 in words is "three hundred eighty-eight million, nine hundred ninety-five thousand, nine hundred eighty-one".