721938666699 has 32 divisors (see below), whose sum is σ = 1087817640000. Its totient is φ = 473133560832.

The previous prime is 721938666671. The next prime is 721938666731. The reversal of 721938666699 is 996666839127.

721938666699 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 721938666699 - 2⁵ = 721938666667 is a prime.

It is not an unprimeable number, because it can be changed into a prime (721938666619) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 534784 + ... + 1315245.

It is an arithmetic number, because the mean of its divisors is an integer number (33994301250).

Almost surely, 2^721938666699 is an apocalyptic number.

721938666699 is a deficient number, since it is larger than the sum of its proper divisors (365878973301).

721938666699 is a wasteful number, since it uses less digits than its factorization.

721938666699 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1850284 (or 1850278 counting only the distinct ones).

The product of its digits is 317447424, while the sum is 72.

The spelling of 721938666699 in words is "seven hundred twenty-one billion, nine hundred thirty-eight million, six hundred sixty-six thousand, six hundred ninety-nine".