77315696640 has 1152 divisors, whose sum is σ = 345080736000. Its totient is φ = 16275603456.

The previous prime is 77315696617. The next prime is 77315696641. The reversal of 77315696640 is 4669651377.

It is a happy number.

77315696640 is a `hidden beast` number, since 7 + 7 + 31 + 569 + 6 + 6 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77315696641) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 176117541 + ... + 176117979.

It is an arithmetic number, because the mean of its divisors is an integer number (299549250).

Almost surely, 2^77315696640 is an apocalyptic number.

77315696640 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 77315696640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (172540368000).

77315696640 is an abundant number, since it is smaller than the sum of its proper divisors (267765039360).

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

77315696640 is a wasteful number, since it uses less digits than its factorization.

77315696640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502 (or 469 counting only the distinct ones).

The product of its (nonzero) digits is 5715360, while the sum is 54.

The spelling of 77315696640 in words is "seventy-seven billion, three hundred fifteen million, six hundred ninety-six thousand, six hundred forty".