77971961652480 has 864 divisors, whose sum is σ = 316538971257600. Its totient is φ = 17712677928960.

The previous prime is 77971961652457. The next prime is 77971961652491. The reversal of 77971961652480 is 8425616917977.

77971961652480 is a `hidden beast` number, since 7 + 7 + 9 + 7 + 1 + 9 + 6 + 16 + 524 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 77971961652399 and 77971961652408.

It is a congruent number.

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, 644011150 + ... + 644132210.

Almost surely, 2^{77971961652480} is an apocalyptic number.

77971961652480 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77971961652480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (158269485628800).

77971961652480 is an abundant number, since it is smaller than the sum of its proper divisors (238567009605120).

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

77971961652480 is a wasteful number, since it uses less digits than its factorization.

77971961652480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121272 (or 121241 counting only the distinct ones).

The product of its (nonzero) digits is 320060160, while the sum is 72.

The spelling of 77971961652480 in words is "seventy-seven trillion, nine hundred seventy-one billion, nine hundred sixty-one million, six hundred fifty-two thousand, four hundred eighty".