72138439396 has 9 divisors (see below), whose sum is σ = 126243209001. Its totient is φ = 36068951112.

The previous prime is 72138439363. The next prime is 72138439409. The reversal of 72138439396 is 69393483127.

The square root of 72138439396 is 268586.

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

It can be written as a sum of positive squares in only one way, i.e., 65326248100 + 6812191296 = 255590^2 + 82536^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 470026 + ... + 604318.

Almost surely, 2^72138439396 is an apocalyptic number.

72138439396 is the 268586-th square number.

It is an amenable number.

72138439396 is a deficient number, since it is larger than the sum of its proper divisors (54104769605).

72138439396 is an frugal number, since it uses more digits than its factorization.

72138439396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268590 (or 134295 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 55.

The spelling of 72138439396 in words is "seventy-two billion, one hundred thirty-eight million, four hundred thirty-nine thousand, three hundred ninety-six".