72217481 has 8 divisors (see below), whose sum is σ = 82645440. Its totient is φ = 61817328.

The previous prime is 72217477. The next prime is 72217487. The reversal of 72217481 is 18471227.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 72217481 - 2² = 72217477 is a prime.

It is a super-2 number, since 2×72217481² = 10430729123970722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72217487) 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, 1046 + ... + 12063.

It is an arithmetic number, because the mean of its divisors is an integer number (10330680).

Almost surely, 2^72217481 is an apocalyptic number.

It is an amenable number.

72217481 is a deficient number, since it is larger than the sum of its proper divisors (10427959).

72217481 is a wasteful number, since it uses less digits than its factorization.

72217481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13903.

The product of its digits is 6272, while the sum is 32.

The square root of 72217481 is about 8498.0869023563. The cubic root of 72217481 is about 416.4352127514.

The spelling of 72217481 in words is "seventy-two million, two hundred seventeen thousand, four hundred eighty-one".