721713541 has 2 divisors, whose sum is σ = 721713542. Its totient is φ = 721713540.

The previous prime is 721713533. The next prime is 721713569. The reversal of 721713541 is 145317127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 651321441 + 70392100 = 25521^2 + 8390^2 .

It is an emirp because it is prime and its reverse (145317127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 721713541 - 2³ = 721713533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721713521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360856770 + 360856771.

It is an arithmetic number, because the mean of its divisors is an integer number (360856771).

Almost surely, 2^721713541 is an apocalyptic number.

It is an amenable number.

721713541 is a deficient number, since it is larger than the sum of its proper divisors (1).

721713541 is an equidigital number, since it uses as much as digits as its factorization.

721713541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5880, while the sum is 31.

The square root of 721713541 is about 26864.7267062220. The cubic root of 721713541 is about 896.9914110669.

The spelling of 721713541 in words is "seven hundred twenty-one million, seven hundred thirteen thousand, five hundred forty-one".