7731389136 has 20 divisors (see below), whose sum is σ = 19972755392. Its totient is φ = 2577129696.

The previous prime is 7731389129. The next prime is 7731389153. The reversal of 7731389136 is 6319831377.

It is a Harshad number since it is a multiple of its sum of digits (48), and also a Moran number because the ratio is a prime number: 161070607 = 7731389136 / (7 + 7 + 3 + 1 + 3 + 8 + 9 + 1 + 3 + 6).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 80535256 + ... + 80535351.

Almost surely, 2^7731389136 is an apocalyptic number.

It is an amenable number.

7731389136 is an abundant number, since it is smaller than the sum of its proper divisors (12241366256).

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

7731389136 is a wasteful number, since it uses less digits than its factorization.

7731389136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161070618 (or 161070612 counting only the distinct ones).

The product of its digits is 571536, while the sum is 48.

The square root of 7731389136 is about 87928.3181688357. The cubic root of 7731389136 is about 1977.3604537970.

The spelling of 7731389136 in words is "seven billion, seven hundred thirty-one million, three hundred eighty-nine thousand, one hundred thirty-six".