72232221 has 8 divisors (see below), whose sum is σ = 97045344. Its totient is φ = 47786960.

The previous prime is 72232187. The next prime is 72232247. The reversal of 72232221 is 12223227.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 72232221 - 2⁷ = 72232093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72232261) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 91506 + ... + 92291.

It is an arithmetic number, because the mean of its divisors is an integer number (12130668).

Almost surely, 2^72232221 is an apocalyptic number.

It is an amenable number.

72232221 is a deficient number, since it is larger than the sum of its proper divisors (24813123).

72232221 is a wasteful number, since it uses less digits than its factorization.

72232221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183931.

The product of its digits is 672, while the sum is 21.

The square root of 72232221 is about 8498.9541121246. The cubic root of 72232221 is about 416.4635430918.

Adding to 72232221 its reverse (12223227), we get a palindrome (84455448).

The spelling of 72232221 in words is "seventy-two million, two hundred thirty-two thousand, two hundred twenty-one".