75361721 has 2 divisors, whose sum is σ = 75361722. Its totient is φ = 75361720.

The previous prime is 75361709. The next prime is 75361763. The reversal of 75361721 is 12716357.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75342400 + 19321 = 8680^2 + 139^2 .

It is a cyclic number.

It is not a de Polignac number, because 75361721 - 2²² = 71167417 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (75361021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37680860 + 37680861.

It is an arithmetic number, because the mean of its divisors is an integer number (37680861).

Almost surely, 2^75361721 is an apocalyptic number.

It is an amenable number.

75361721 is a deficient number, since it is larger than the sum of its proper divisors (1).

75361721 is an equidigital number, since it uses as much as digits as its factorization.

75361721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8820, while the sum is 32.

The square root of 75361721 is about 8681.1128894860. The cubic root of 75361721 is about 422.3932174149.

The spelling of 75361721 in words is "seventy-five million, three hundred sixty-one thousand, seven hundred twenty-one".