77979911680 has 240 divisors, whose sum is σ = 206602870320. Its totient is φ = 28205957120.

The previous prime is 77979911657. The next prime is 77979911707. The reversal of 77979911680 is 8611997977.

It is a Harshad number since it is a multiple of its sum of digits (64).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70314966 + ... + 70316074.

It is an arithmetic number, because the mean of its divisors is an integer number (860845293).

Almost surely, 2^77979911680 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 77979911680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103301435160).

77979911680 is an abundant number, since it is smaller than the sum of its proper divisors (128622958640).

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

77979911680 is a wasteful number, since it uses less digits than its factorization.

77979911680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381 (or 1354 counting only the distinct ones).

The product of its (nonzero) digits is 12002256, while the sum is 64.

The spelling of 77979911680 in words is "seventy-seven billion, nine hundred seventy-nine million, nine hundred eleven thousand, six hundred eighty".