72672217 has 4 divisors (see below), whose sum is σ = 73160100. Its totient is φ = 72184336.

The previous prime is 72672209. The next prime is 72672241. The reversal of 72672217 is 71227627.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71227627 = 37 ⋅1925071.

It can be written as a sum of positive squares in 2 ways, for example, as 46498761 + 26173456 = 6819^2 + 5116^2 .

It is a cyclic number.

It is not a de Polignac number, because 72672217 - 2³ = 72672209 is a prime.

It is a super-2 number, since 2×72672217² = 10562502247390178, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72672517) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 243718 + ... + 244015.

It is an arithmetic number, because the mean of its divisors is an integer number (18290025).

Almost surely, 2^72672217 is an apocalyptic number.

It is an amenable number.

72672217 is a deficient number, since it is larger than the sum of its proper divisors (487883).

72672217 is a wasteful number, since it uses less digits than its factorization.

72672217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487882.

The product of its digits is 16464, while the sum is 34.

The square root of 72672217 is about 8524.8001149587. The cubic root of 72672217 is about 417.3074484694.

The spelling of 72672217 in words is "seventy-two million, six hundred seventy-two thousand, two hundred seventeen".