388707990 has 64 divisors (see below), whose sum is σ = 1022388480. Its totient is φ = 93799040.

The previous prime is 388707971. The next prime is 388708057. The reversal of 388707990 is 99707883.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 72316 + ... + 77504.

It is an arithmetic number, because the mean of its divisors is an integer number (15974820).

Almost surely, 2^388707990 is an apocalyptic number.

388707990 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 388707990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (511194240).

388707990 is an abundant number, since it is smaller than the sum of its proper divisors (633680490).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

388707990 is a wasteful number, since it uses less digits than its factorization.

388707990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5437.

The product of its (nonzero) digits is 762048, while the sum is 51.

The square root of 388707990 is about 19715.6787861844. The cubic root of 388707990 is about 729.8066605021.

The spelling of 388707990 in words is "three hundred eighty-eight million, seven hundred seven thousand, nine hundred ninety".