74115721 has 2 divisors, whose sum is σ = 74115722. Its totient is φ = 74115720.

The previous prime is 74115709. The next prime is 74115731. The reversal of 74115721 is 12751147.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74046025 + 69696 = 8605^2 + 264^2 .

It is a cyclic number.

It is not a de Polignac number, because 74115721 - 2⁷ = 74115593 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 74115721.

It is not a weakly prime, because it can be changed into another prime (74115731) 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, 37057860 + 37057861.

It is an arithmetic number, because the mean of its divisors is an integer number (37057861).

Almost surely, 2^74115721 is an apocalyptic number.

It is an amenable number.

74115721 is a deficient number, since it is larger than the sum of its proper divisors (1).

74115721 is an equidigital number, since it uses as much as digits as its factorization.

74115721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1960, while the sum is 28.

The square root of 74115721 is about 8609.0487860158. The cubic root of 74115721 is about 420.0523763101.

Adding to 74115721 its reverse (12751147), we get a palindrome (86866868).

The spelling of 74115721 in words is "seventy-four million, one hundred fifteen thousand, seven hundred twenty-one".