722351691981 has 6 divisors (see below), whose sum is σ = 1043396888430. Its totient is φ = 481567794648.

The previous prime is 722351691967. The next prime is 722351692001. The reversal of 722351691981 is 189196153227.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 720179665956 + 2172026025 = 848634^2 + 46605^2 .

It is not a de Polignac number, because 722351691981 - 2²⁵ = 722318137549 is a prime.

It is a super-2 number, since 2×722351691981² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (722351691781) 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 5 ways as a sum of consecutive naturals, for example, 40130649546 + ... + 40130649563.

It is an arithmetic number, because the mean of its divisors is an integer number (173899481405).

Almost surely, 2^722351691981 is an apocalyptic number.

It is an amenable number.

722351691981 is a deficient number, since it is larger than the sum of its proper divisors (321045196449).

722351691981 is a wasteful number, since it uses less digits than its factorization.

722351691981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80261299115 (or 80261299112 counting only the distinct ones).

The product of its digits is 1632960, while the sum is 54.

The spelling of 722351691981 in words is "seven hundred twenty-two billion, three hundred fifty-one million, six hundred ninety-one thousand, nine hundred eighty-one".