721543634731069 has 2 divisors, whose sum is σ = 721543634731070. Its totient is φ = 721543634731068.

The previous prime is 721543634731039. The next prime is 721543634731097. The reversal of 721543634731069 is 960137436345127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 692997727522500 + 28545907208569 = 26324850^2 + 5342837^2 .

It is a cyclic number.

It is not a de Polignac number, because 721543634731069 - 2⁵ = 721543634731037 is a prime.

It is a super-2 number, since 2×721543634731069² (a number of 31 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 721543634730998 and 721543634731016.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721543634731039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360771817365534 + 360771817365535.

It is an arithmetic number, because the mean of its divisors is an integer number (360771817365535).

Almost surely, 2^{721543634731069} is an apocalyptic number.

It is an amenable number.

721543634731069 is a deficient number, since it is larger than the sum of its proper divisors (1).

721543634731069 is an equidigital number, since it uses as much as digits as its factorization.

721543634731069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 68584320, while the sum is 61.

The spelling of 721543634731069 in words is "seven hundred twenty-one trillion, five hundred forty-three billion, six hundred thirty-four million, seven hundred thirty-one thousand, sixty-nine".