72431495161 has 3 divisors (see below), whose sum is σ = 72431764293. Its totient is φ = 72431226030.

The previous prime is 72431495159. The next prime is 72431495167. The reversal of 72431495161 is 16159413427.

It is a happy number.

The square root of 72431495161 is 269131.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 72431495161 - 2¹ = 72431495159 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72431495167) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 134566 + ... + 403696.

It is an arithmetic number, because the mean of its divisors is an integer number (24143921431).

Almost surely, 2^72431495161 is an apocalyptic number.

72431495161 is the 269131-st square number.

72431495161 is the 134566-th centered octagonal number.

It is an amenable number.

72431495161 is a deficient number, since it is larger than the sum of its proper divisors (269132).

72431495161 is an frugal number, since it uses more digits than its factorization.

72431495161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 538262 (or 269131 counting only the distinct ones).

The product of its digits is 181440, while the sum is 43.

The spelling of 72431495161 in words is "seventy-two billion, four hundred thirty-one million, four hundred ninety-five thousand, one hundred sixty-one".