72879217 has 4 divisors (see below), whose sum is σ = 73148416. Its totient is φ = 72610020.

The previous prime is 72879211. The next prime is 72879239. The reversal of 72879217 is 71297827.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 71297827 = 43 ⋅1658089.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72879217 is a prime.

It is a super-2 number, since 2×72879217² = 10622760541066178, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72879211) 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, 134193 + ... + 134734.

It is an arithmetic number, because the mean of its divisors is an integer number (18287104).

Almost surely, 2^72879217 is an apocalyptic number.

It is an amenable number.

72879217 is a deficient number, since it is larger than the sum of its proper divisors (269199).

72879217 is a wasteful number, since it uses less digits than its factorization.

72879217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269198.

The product of its digits is 98784, while the sum is 43.

The square root of 72879217 is about 8536.9325287248. The cubic root of 72879217 is about 417.7032932518.

The spelling of 72879217 in words is "seventy-two million, eight hundred seventy-nine thousand, two hundred seventeen".