72217557 has 12 divisors (see below), whose sum is σ = 104401440. Its totient is φ = 48104808.

The previous prime is 72217531. The next prime is 72217571. The reversal of 72217557 is 75571227.

It is not a de Polignac number, because 72217557 - 2¹¹ = 72215509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72217577) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11458 + ... + 16604.

It is an arithmetic number, because the mean of its divisors is an integer number (8700120).

Almost surely, 2^72217557 is an apocalyptic number.

It is an amenable number.

72217557 is a deficient number, since it is larger than the sum of its proper divisors (32183883).

72217557 is a wasteful number, since it uses less digits than its factorization.

72217557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6712 (or 6709 counting only the distinct ones).

The product of its digits is 34300, while the sum is 36.

The square root of 72217557 is about 8498.0913739498. The cubic root of 72217557 is about 416.4353588336.

The spelling of 72217557 in words is "seventy-two million, two hundred seventeen thousand, five hundred fifty-seven".