78742388731 has 16 divisors (see below), whose sum is σ = 84670594560. Its totient is φ = 72993333600.

The previous prime is 78742388717. The next prime is 78742388741. The reversal of 78742388731 is 13788324787.

It is not a de Polignac number, because 78742388731 - 2²³ = 78734000123 is a prime.

It is a super-2 number, since 2×78742388731² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78742388741) 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, 5083260 + ... + 5098726.

It is an arithmetic number, because the mean of its divisors is an integer number (5291912160).

Almost surely, 2^78742388731 is an apocalyptic number.

78742388731 is a deficient number, since it is larger than the sum of its proper divisors (5928205829).

78742388731 is a wasteful number, since it uses less digits than its factorization.

78742388731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21234.

The product of its digits is 12644352, while the sum is 58.

The spelling of 78742388731 in words is "seventy-eight billion, seven hundred forty-two million, three hundred eighty-eight thousand, seven hundred thirty-one".