75013807721 has 2 divisors, whose sum is σ = 75013807722. Its totient is φ = 75013807720.

The previous prime is 75013807669. The next prime is 75013807741. The reversal of 75013807721 is 12770831057.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52503306496 + 22510501225 = 229136^2 + 150035^2 .

It is a cyclic number.

It is not a de Polignac number, because 75013807721 - 2¹⁸ = 75013545577 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (75013807741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37506903860 + 37506903861.

It is an arithmetic number, because the mean of its divisors is an integer number (37506903861).

Almost surely, 2^75013807721 is an apocalyptic number.

It is an amenable number.

75013807721 is a deficient number, since it is larger than the sum of its proper divisors (1).

75013807721 is an equidigital number, since it uses as much as digits as its factorization.

75013807721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 82320, while the sum is 41.

The spelling of 75013807721 in words is "seventy-five billion, thirteen million, eight hundred seven thousand, seven hundred twenty-one".