721320079 has 2 divisors, whose sum is σ = 721320080. Its totient is φ = 721320078.

The previous prime is 721320073. The next prime is 721320107. The reversal of 721320079 is 970023127.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 721320079 - 2³ = 721320071 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 721320079.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721320071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360660039 + 360660040.

It is an arithmetic number, because the mean of its divisors is an integer number (360660040).

Almost surely, 2^721320079 is an apocalyptic number.

721320079 is a deficient number, since it is larger than the sum of its proper divisors (1).

721320079 is an equidigital number, since it uses as much as digits as its factorization.

721320079 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5292, while the sum is 31.

The square root of 721320079 is about 26857.4026852933. The cubic root of 721320079 is about 896.8283749172.

The spelling of 721320079 in words is "seven hundred twenty-one million, three hundred twenty thousand, seventy-nine".