723115664521 has 4 divisors (see below), whose sum is σ = 724209637444. Its totient is φ = 722021691600.

The previous prime is 723115664483. The next prime is 723115664539. The reversal of 723115664521 is 125466511327.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 477293066496 + 245822598025 = 690864^2 + 495805^2 .

It is a cyclic number.

It is not a de Polignac number, because 723115664521 - 2⁹ = 723115664009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (723115668521) 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 in 3 ways as a sum of consecutive naturals, for example, 546985470 + ... + 546986791.

It is an arithmetic number, because the mean of its divisors is an integer number (181052409361).

Almost surely, 2^723115664521 is an apocalyptic number.

It is an amenable number.

723115664521 is a deficient number, since it is larger than the sum of its proper divisors (1093972923).

723115664521 is a wasteful number, since it uses less digits than its factorization.

723115664521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1093972922.

The product of its digits is 302400, while the sum is 43.

The spelling of 723115664521 in words is "seven hundred twenty-three billion, one hundred fifteen million, six hundred sixty-four thousand, five hundred twenty-one".