72153221 has 8 divisors (see below), whose sum is σ = 82876800. Its totient is φ = 61533648.

The previous prime is 72153217. The next prime is 72153239. The reversal of 72153221 is 12235127.

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 72153221 - 2² = 72153217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72153281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24506 + ... + 27291.

It is an arithmetic number, because the mean of its divisors is an integer number (10359600).

Almost surely, 2^72153221 is an apocalyptic number.

It is an amenable number.

72153221 is a deficient number, since it is larger than the sum of its proper divisors (10723579).

72153221 is a wasteful number, since it uses less digits than its factorization.

72153221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52003.

The product of its digits is 840, while the sum is 23.

The square root of 72153221 is about 8494.3052099627. The cubic root of 72153221 is about 416.3116597118.

Adding to 72153221 its reverse (12235127), we get a palindrome (84388348).

The spelling of 72153221 in words is "seventy-two million, one hundred fifty-three thousand, two hundred twenty-one".