72115557 has 8 divisors (see below), whose sum is σ = 100334784. Its totient is φ = 45986688.

The previous prime is 72115529. The next prime is 72115591. The reversal of 72115557 is 75551127.

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

It is not a de Polignac number, because 72115557 - 2¹² = 72111461 is a prime.

It is a super-2 number, since 2×72115557² = 10401307122840498, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72115957) 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, 522508 + ... + 522645.

It is an arithmetic number, because the mean of its divisors is an integer number (12541848).

Almost surely, 2^72115557 is an apocalyptic number.

It is an amenable number.

72115557 is a deficient number, since it is larger than the sum of its proper divisors (28219227).

72115557 is a wasteful number, since it uses less digits than its factorization.

72115557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1045179.

The product of its digits is 12250, while the sum is 33.

The square root of 72115557 is about 8492.0879058097. The cubic root of 72115557 is about 416.2392088393.

The spelling of 72115557 in words is "seventy-two million, one hundred fifteen thousand, five hundred fifty-seven".