72220251 has 4 divisors (see below), whose sum is σ = 96293672. Its totient is φ = 48146832.

The previous prime is 72220249. The next prime is 72220259. The reversal of 72220251 is 15202227.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 72220251 - 2¹ = 72220249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72220259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12036706 + ... + 12036711.

It is an arithmetic number, because the mean of its divisors is an integer number (24073418).

Almost surely, 2^72220251 is an apocalyptic number.

72220251 is a deficient number, since it is larger than the sum of its proper divisors (24073421).

72220251 is a wasteful number, since it uses less digits than its factorization.

72220251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24073420.

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 72220251 is about 8498.2498786515. The cubic root of 72220251 is about 416.4405369969.

Adding to 72220251 its reverse (15202227), we get a palindrome (87422478).

The spelling of 72220251 in words is "seventy-two million, two hundred twenty thousand, two hundred fifty-one".