721120011165 has 12 divisors (see below), whose sum is σ = 1249941352764. Its totient is φ = 384597339264.

The previous prime is 721120011137. The next prime is 721120011169. The reversal of 721120011165 is 561110021127.

It can be written as a sum of positive squares in 2 ways, for example, as 387603366084 + 333516645081 = 622578^2 + 577509^2 .

It is not a de Polignac number, because 721120011165 - 2¹⁹ = 721119486877 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721120011169) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8012444524 + ... + 8012444613.

It is an arithmetic number, because the mean of its divisors is an integer number (104161779397).

Almost surely, 2^721120011165 is an apocalyptic number.

It is an amenable number.

721120011165 is a deficient number, since it is larger than the sum of its proper divisors (528821341599).

721120011165 is a wasteful number, since it uses less digits than its factorization.

721120011165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16024889148 (or 16024889145 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 27.

The spelling of 721120011165 in words is "seven hundred twenty-one billion, one hundred twenty million, eleven thousand, one hundred sixty-five".