77089961520 has 720 divisors, whose sum is σ = 317935546656. Its totient is φ = 17244057600.

The previous prime is 77089961471. The next prime is 77089961539. The reversal of 77089961520 is 2516998077.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 30577860 + ... + 30580380.

Almost surely, 2^77089961520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77089961520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (158967773328).

77089961520 is an abundant number, since it is smaller than the sum of its proper divisors (240845585136).

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

77089961520 is a wasteful number, since it uses less digits than its factorization.

77089961520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2584 (or 2555 counting only the distinct ones).

The product of its (nonzero) digits is 1905120, while the sum is 54.

The spelling of 77089961520 in words is "seventy-seven billion, eighty-nine million, nine hundred sixty-one thousand, five hundred twenty".