72138139169 has 16 divisors (see below), whose sum is σ = 76008025296. Its totient is φ = 68374425600.

The previous prime is 72138139163. The next prime is 72138139187. The reversal of 72138139169 is 96193183127.

It can be written as a sum of positive squares in 8 ways, for example, as 28336672225 + 43801466944 = 168335^2 + 209288^2 .

It is a cyclic number.

It is not a de Polignac number, because 72138139169 - 2⁸ = 72138138913 is a prime.

It is a super-2 number, since 2×72138139169² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72138139163) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 991889 + ... + 1062129.

It is an arithmetic number, because the mean of its divisors is an integer number (4750501581).

Almost surely, 2^72138139169 is an apocalyptic number.

It is an amenable number.

72138139169 is a deficient number, since it is larger than the sum of its proper divisors (3869886127).

72138139169 is a wasteful number, since it uses less digits than its factorization.

72138139169 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70996.

The product of its digits is 489888, while the sum is 50.

The spelling of 72138139169 in words is "seventy-two billion, one hundred thirty-eight million, one hundred thirty-nine thousand, one hundred sixty-nine".