72139913917 has 4 divisors (see below), whose sum is σ = 72582490240. Its totient is φ = 71697337596.

The previous prime is 72139913827. The next prime is 72139913971. The reversal of 72139913917 is 71931993127.

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 a de Polignac number, because none of the positive numbers 2^k-72139913917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72139913017) 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, 221287917 + ... + 221288242.

It is an arithmetic number, because the mean of its divisors is an integer number (18145622560).

Almost surely, 2^72139913917 is an apocalyptic number.

It is an amenable number.

72139913917 is a deficient number, since it is larger than the sum of its proper divisors (442576323).

72139913917 is a wasteful number, since it uses less digits than its factorization.

72139913917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 442576322.

The product of its digits is 642978, while the sum is 52.

The spelling of 72139913917 in words is "seventy-two billion, one hundred thirty-nine million, nine hundred thirteen thousand, nine hundred seventeen".