77891357940 has 96 divisors (see below), whose sum is σ = 248267206656. Its totient is φ = 18061760640.

The previous prime is 77891357923. The next prime is 77891357959. The reversal of 77891357940 is 4975319877.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2550412 + ... + 2580771.

It is an arithmetic number, because the mean of its divisors is an integer number (2586116736).

Almost surely, 2^77891357940 is an apocalyptic number.

It is an amenable number.

77891357940 is an abundant number, since it is smaller than the sum of its proper divisors (170375848716).

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

77891357940 is a wasteful number, since it uses less digits than its factorization.

77891357940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5131229 (or 5131227 counting only the distinct ones).

The product of its (nonzero) digits is 13335840, while the sum is 60.

The spelling of 77891357940 in words is "seventy-seven billion, eight hundred ninety-one million, three hundred fifty-seven thousand, nine hundred forty".