872497221 has 4 divisors (see below), whose sum is σ = 1163329632. Its totient is φ = 581664812.

The previous prime is 872497217. The next prime is 872497229. The reversal of 872497221 is 122794278.

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.

It is a cyclic number.

It is not a de Polignac number, because 872497221 - 2² = 872497217 is a prime.

It is a super-2 number, since 2×872497221² = 1522502801305445682, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (872497229) 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, 145416201 + ... + 145416206.

It is an arithmetic number, because the mean of its divisors is an integer number (290832408).

Almost surely, 2^872497221 is an apocalyptic number.

It is an amenable number.

872497221 is a deficient number, since it is larger than the sum of its proper divisors (290832411).

872497221 is a wasteful number, since it uses less digits than its factorization.

872497221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290832410.

The product of its digits is 112896, while the sum is 42.

The square root of 872497221 is about 29538.0639345235. The cubic root of 872497221 is about 955.5527883405.

The spelling of 872497221 in words is "eight hundred seventy-two million, four hundred ninety-seven thousand, two hundred twenty-one".