78749723522 has 54 divisors (see below), whose sum is σ = 126175309659. Its totient is φ = 36860542560.

The previous prime is 78749723513. The next prime is 78749723527. The reversal of 78749723522 is 22532794787.

It can be written as a sum of positive squares in 5 ways, for example, as 76995705361 + 1754018161 = 277481^2 + 41881^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=198431.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78749723527) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 455200628 + ... + 455200800.

Almost surely, 2^78749723522 is an apocalyptic number.

78749723522 is a deficient number, since it is larger than the sum of its proper divisors (47425586137).

78749723522 is an equidigital number, since it uses as much as digits as its factorization.

78749723522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 484 (or 243 counting only the distinct ones).

The product of its digits is 11854080, while the sum is 56.

The spelling of 78749723522 in words is "seventy-eight billion, seven hundred forty-nine million, seven hundred twenty-three thousand, five hundred twenty-two".