72115511551 has 4 divisors (see below), whose sum is σ = 72130562352. Its totient is φ = 72100460752.

The previous prime is 72115511549. The next prime is 72115511557. The reversal of 72115511551 is 15511551127.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 72115511551 - 2¹ = 72115511549 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 (72115511557) 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, 7518211 + ... + 7527796.

It is an arithmetic number, because the mean of its divisors is an integer number (18032640588).

Almost surely, 2^72115511551 is an apocalyptic number.

72115511551 is a deficient number, since it is larger than the sum of its proper divisors (15050801).

72115511551 is a wasteful number, since it uses less digits than its factorization.

72115511551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15050800.

The product of its digits is 8750, while the sum is 34.

The spelling of 72115511551 in words is "seventy-two billion, one hundred fifteen million, five hundred eleven thousand, five hundred fifty-one".