388816720 has 40 divisors (see below), whose sum is σ = 928438344. Its totient is φ = 151322112.

The previous prime is 388816711. The next prime is 388816789. The reversal of 388816720 is 27618883.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 64384576 + 324432144 = 8024^2 + 18012^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62719 + ... + 68638.

Almost surely, 2^388816720 is an apocalyptic number.

It is an amenable number.

388816720 is an abundant number, since it is smaller than the sum of its proper divisors (539621624).

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

388816720 is a wasteful number, since it uses less digits than its factorization.

388816720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131407 (or 131401 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 43.

The square root of 388816720 is about 19718.4360434594. The cubic root of 388816720 is about 729.8747017075.

The spelling of 388816720 in words is "three hundred eighty-eight million, eight hundred sixteen thousand, seven hundred twenty".