721379497 has 2 divisors, whose sum is σ = 721379498. Its totient is φ = 721379496.

The previous prime is 721379447. The next prime is 721379501. The reversal of 721379497 is 794973127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 692531856 + 28847641 = 26316^2 + 5371^2 .

It is a cyclic number.

It is not a de Polignac number, because 721379497 - 2⁷ = 721379369 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 721379497.

It is not a weakly prime, because it can be changed into another prime (721379447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360689748 + 360689749.

It is an arithmetic number, because the mean of its divisors is an integer number (360689749).

Almost surely, 2^721379497 is an apocalyptic number.

It is an amenable number.

721379497 is a deficient number, since it is larger than the sum of its proper divisors (1).

721379497 is an equidigital number, since it uses as much as digits as its factorization.

721379497 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 666792, while the sum is 49.

The square root of 721379497 is about 26858.5088379828. The cubic root of 721379497 is about 896.8529993462.

The spelling of 721379497 in words is "seven hundred twenty-one million, three hundred seventy-nine thousand, four hundred ninety-seven".