72147818 has 8 divisors (see below), whose sum is σ = 108338148. Its totient is φ = 36035104.

The previous prime is 72147809. The next prime is 72147869. The reversal of 72147818 is 81874127.

It can be written as a sum of positive squares in 2 ways, for example, as 61105489 + 11042329 = 7817^2 + 3323^2 .

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

It is a super-2 number, since 2×72147818² = 10410615284322248, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

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 3 ways as a sum of consecutive naturals, for example, 17021 + ... + 20832.

Almost surely, 2^72147818 is an apocalyptic number.

72147818 is a deficient number, since it is larger than the sum of its proper divisors (36190330).

72147818 is a wasteful number, since it uses less digits than its factorization.

72147818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38808.

The product of its digits is 25088, while the sum is 38.

The square root of 72147818 is about 8493.9871674026. The cubic root of 72147818 is about 416.3012679926.

The spelling of 72147818 in words is "seventy-two million, one hundred forty-seven thousand, eight hundred eighteen".