76721791457 has 4 divisors (see below), whose sum is σ = 76722353856. Its totient is φ = 76721229060.

The previous prime is 76721791451. The next prime is 76721791459. The reversal of 76721791457 is 75419712767.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 76721791457 - 2⁴ = 76721791441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (76721791451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67868 + ... + 397554.

It is an arithmetic number, because the mean of its divisors is an integer number (19180588464).

Almost surely, 2^76721791457 is an apocalyptic number.

It is an amenable number.

76721791457 is a deficient number, since it is larger than the sum of its proper divisors (562399).

76721791457 is a wasteful number, since it uses less digits than its factorization.

76721791457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 562398.

The product of its digits is 5186160, while the sum is 56.

The spelling of 76721791457 in words is "seventy-six billion, seven hundred twenty-one million, seven hundred ninety-one thousand, four hundred fifty-seven".