721320756727 has 2 divisors, whose sum is σ = 721320756728. Its totient is φ = 721320756726.

The previous prime is 721320756703. The next prime is 721320756743. The reversal of 721320756727 is 727657023127.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-721320756727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721320726727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360660378363 + 360660378364.

It is an arithmetic number, because the mean of its divisors is an integer number (360660378364).

Almost surely, 2^721320756727 is an apocalyptic number.

721320756727 is a deficient number, since it is larger than the sum of its proper divisors (1).

721320756727 is an equidigital number, since it uses as much as digits as its factorization.

721320756727 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728720, while the sum is 49.

The spelling of 721320756727 in words is "seven hundred twenty-one billion, three hundred twenty million, seven hundred fifty-six thousand, seven hundred twenty-seven".