72817945 has 8 divisors (see below), whose sum is σ = 88686144. Its totient is φ = 57384624.

The previous prime is 72817933. The next prime is 72817967. The reversal of 72817945 is 54971827.

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 72817945 - 2¹⁹ = 72293657 is a prime.

It is a super-2 number, since 2×72817945² = 10604906228046050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 108349 + ... + 109018.

It is an arithmetic number, because the mean of its divisors is an integer number (11085768).

Almost surely, 2^72817945 is an apocalyptic number.

It is an amenable number.

72817945 is a deficient number, since it is larger than the sum of its proper divisors (15868199).

72817945 is a wasteful number, since it uses less digits than its factorization.

72817945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217439.

The product of its digits is 141120, while the sum is 43.

The square root of 72817945 is about 8533.3431315048. The cubic root of 72817945 is about 417.5862013792.

The spelling of 72817945 in words is "seventy-two million, eight hundred seventeen thousand, nine hundred forty-five".