72221873 has 2 divisors, whose sum is σ = 72221874. Its totient is φ = 72221872.

The previous prime is 72221837. The next prime is 72221887. The reversal of 72221873 is 37812227.

Together with previous prime (72221837) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37847104 + 34374769 = 6152^2 + 5863^2 .

It is a cyclic number.

It is not a de Polignac number, because 72221873 - 2¹⁰ = 72220849 is a prime.

It is not a weakly prime, because it can be changed into another prime (72221813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36110936 + 36110937.

It is an arithmetic number, because the mean of its divisors is an integer number (36110937).

Almost surely, 2^72221873 is an apocalyptic number.

It is an amenable number.

72221873 is a deficient number, since it is larger than the sum of its proper divisors (1).

72221873 is an equidigital number, since it uses as much as digits as its factorization.

72221873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9408, while the sum is 32.

The square root of 72221873 is about 8498.3453095294. The cubic root of 72221873 is about 416.4436545966.

The spelling of 72221873 in words is "seventy-two million, two hundred twenty-one thousand, eight hundred seventy-three".