721727617679 has 2 divisors, whose sum is σ = 721727617680. Its totient is φ = 721727617678.

The previous prime is 721727617649. The next prime is 721727617687. The reversal of 721727617679 is 976716727127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721727617679 - 2³² = 717432650383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721727617609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360863808839 + 360863808840.

It is an arithmetic number, because the mean of its divisors is an integer number (360863808840).

Almost surely, 2^721727617679 is an apocalyptic number.

721727617679 is a deficient number, since it is larger than the sum of its proper divisors (1).

721727617679 is an equidigital number, since it uses as much as digits as its factorization.

721727617679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21781872, while the sum is 62.

The spelling of 721727617679 in words is "seven hundred twenty-one billion, seven hundred twenty-seven million, six hundred seventeen thousand, six hundred seventy-nine".