72221497 has 2 divisors, whose sum is σ = 72221498. Its totient is φ = 72221496.

The previous prime is 72221483. The next prime is 72221503. The reversal of 72221497 is 79412227.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63107136 + 9114361 = 7944^2 + 3019^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72221497 is a prime.

It is not a weakly prime, because it can be changed into another prime (72221477) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36110748 + 36110749.

It is an arithmetic number, because the mean of its divisors is an integer number (36110749).

Almost surely, 2^72221497 is an apocalyptic number.

It is an amenable number.

72221497 is a deficient number, since it is larger than the sum of its proper divisors (1).

72221497 is an equidigital number, since it uses as much as digits as its factorization.

72221497 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14112, while the sum is 34.

The square root of 72221497 is about 8498.3231875471. The cubic root of 72221497 is about 416.4429319019.

The spelling of 72221497 in words is "seventy-two million, two hundred twenty-one thousand, four hundred ninety-seven".