721453697 has 2 divisors, whose sum is σ = 721453698. Its totient is φ = 721453696.

The previous prime is 721453687. The next prime is 721453703. The reversal of 721453697 is 796354127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 413064976 + 308388721 = 20324^2 + 17561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-721453697 is a prime.

It is not a weakly prime, because it can be changed into another prime (721453657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360726848 + 360726849.

It is an arithmetic number, because the mean of its divisors is an integer number (360726849).

Almost surely, 2^721453697 is an apocalyptic number.

It is an amenable number.

721453697 is a deficient number, since it is larger than the sum of its proper divisors (1).

721453697 is an equidigital number, since it uses as much as digits as its factorization.

721453697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 317520, while the sum is 44.

The square root of 721453697 is about 26859.8901151885. The cubic root of 721453697 is about 896.8837479380.

The spelling of 721453697 in words is "seven hundred twenty-one million, four hundred fifty-three thousand, six hundred ninety-seven".