76913800721 has 2 divisors, whose sum is σ = 76913800722. Its totient is φ = 76913800720.

The previous prime is 76913800681. The next prime is 76913800741. The reversal of 76913800721 is 12700831967.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48560292496 + 28353508225 = 220364^2 + 168385^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-76913800721 is a prime.

It is not a weakly prime, because it can be changed into another prime (76913800741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38456900360 + 38456900361.

It is an arithmetic number, because the mean of its divisors is an integer number (38456900361).

Almost surely, 2^76913800721 is an apocalyptic number.

It is an amenable number.

76913800721 is a deficient number, since it is larger than the sum of its proper divisors (1).

76913800721 is an equidigital number, since it uses as much as digits as its factorization.

76913800721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 127008, while the sum is 44.

The spelling of 76913800721 in words is "seventy-six billion, nine hundred thirteen million, eight hundred thousand, seven hundred twenty-one".