72739181 has 4 divisors (see below), whose sum is σ = 72949152. Its totient is φ = 72529212.

The previous prime is 72739157. The next prime is 72739211. The reversal of 72739181 is 18193727.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72739181 - 2¹⁰ = 72738157 is a prime.

It is a super-2 number, since 2×72739181² = 10581976905101522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72739081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104465 + ... + 105158.

It is an arithmetic number, because the mean of its divisors is an integer number (18237288).

Almost surely, 2^72739181 is an apocalyptic number.

It is an amenable number.

72739181 is a deficient number, since it is larger than the sum of its proper divisors (209971).

72739181 is a wasteful number, since it uses less digits than its factorization.

72739181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209970.

The product of its digits is 21168, while the sum is 38.

The square root of 72739181 is about 8528.7268100227. The cubic root of 72739181 is about 417.4355854583.

The spelling of 72739181 in words is "seventy-two million, seven hundred thirty-nine thousand, one hundred eighty-one".