72418109 has 4 divisors (see below), whose sum is σ = 72447516. Its totient is φ = 72388704.

The previous prime is 72418103. The next prime is 72418141. The reversal of 72418109 is 90181427.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33605209 + 38812900 = 5797^2 + 6230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72418109 is a prime.

It is a super-2 number, since 2×72418109² = 10488765022271762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72418103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10634 + ... + 16059.

It is an arithmetic number, because the mean of its divisors is an integer number (18111879).

Almost surely, 2^72418109 is an apocalyptic number.

It is an amenable number.

72418109 is a deficient number, since it is larger than the sum of its proper divisors (29407).

72418109 is a wasteful number, since it uses less digits than its factorization.

72418109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29406.

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 72418109 is about 8509.8830191725. The cubic root of 72418109 is about 416.8204902627.

It can be divided in two parts, 72418 and 109, that added together give a palindrome (72527).

The spelling of 72418109 in words is "seventy-two million, four hundred eighteen thousand, one hundred nine".