72309221731 has 8 divisors (see below), whose sum is σ = 74805688800. Its totient is φ = 69812957760.

The previous prime is 72309221717. The next prime is 72309221741. The reversal of 72309221731 is 13712290327.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 72309221731 - 2²¹ = 72307124579 is a prime.

It is a super-2 number, since 2×72309221731² (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 (72309221741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1177650 + ... + 1237528.

It is an arithmetic number, because the mean of its divisors is an integer number (9350711100).

Almost surely, 2^72309221731 is an apocalyptic number.

72309221731 is a deficient number, since it is larger than the sum of its proper divisors (2496467069).

72309221731 is a wasteful number, since it uses less digits than its factorization.

72309221731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101549.

The product of its (nonzero) digits is 31752, while the sum is 37.

The spelling of 72309221731 in words is "seventy-two billion, three hundred nine million, two hundred twenty-one thousand, seven hundred thirty-one".