77476021920 has 576 divisors, whose sum is σ = 295435340928. Its totient is φ = 18330624000.

The previous prime is 77476021873. The next prime is 77476021949. The reversal of 77476021920 is 2912067477.

77476021920 is a `hidden beast` number, since 7 + 7 + 4 + 7 + 602 + 19 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 174889219 + ... + 174889661.

It is an arithmetic number, because the mean of its divisors is an integer number (512908578).

Almost surely, 2^77476021920 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 77476021920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147717670464).

77476021920 is an abundant number, since it is smaller than the sum of its proper divisors (217959319008).

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

77476021920 is a wasteful number, since it uses less digits than its factorization.

77476021920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 717 (or 706 counting only the distinct ones).

The product of its (nonzero) digits is 296352, while the sum is 45.

The spelling of 77476021920 in words is "seventy-seven billion, four hundred seventy-six million, twenty-one thousand, nine hundred twenty".