77921395200 has 960 divisors, whose sum is σ = 316622592000. Its totient is φ = 18612633600.

The previous prime is 77921395193. The next prime is 77921395217. The reversal of 77921395200 is 259312977.

77921395200 is a `hidden beast` number, since 7 + 7 + 92 + 1 + 39 + 520 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 391564701 + ... + 391564899.

It is an arithmetic number, because the mean of its divisors is an integer number (329815200).

Almost surely, 2^77921395200 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 77921395200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (158311296000).

77921395200 is an abundant number, since it is smaller than the sum of its proper divisors (238701196800).

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

77921395200 is a wasteful number, since it uses less digits than its factorization.

77921395200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350 (or 323 counting only the distinct ones).

The product of its (nonzero) digits is 238140, while the sum is 45.

The spelling of 77921395200 in words is "seventy-seven billion, nine hundred twenty-one million, three hundred ninety-five thousand, two hundred".