72249391 has 2 divisors, whose sum is σ = 72249392. Its totient is φ = 72249390.

The previous prime is 72249367. The next prime is 72249403. The reversal of 72249391 is 19394227.

It is a strong prime.

It is an emirp because it is prime and its reverse (19394227) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72249391 - 2⁷ = 72249263 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72249391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72249311) 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 as a sum of consecutive naturals, namely, 36124695 + 36124696.

It is an arithmetic number, because the mean of its divisors is an integer number (36124696).

Almost surely, 2^72249391 is an apocalyptic number.

72249391 is a deficient number, since it is larger than the sum of its proper divisors (1).

72249391 is an equidigital number, since it uses as much as digits as its factorization.

72249391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 37.

The square root of 72249391 is about 8499.9641763951. The cubic root of 72249391 is about 416.4965390431.

The spelling of 72249391 in words is "seventy-two million, two hundred forty-nine thousand, three hundred ninety-one".