7500525721 has 6 divisors (see below), whose sum is σ = 8121871230. Its totient is φ = 6923562048.

The previous prime is 7500525713. The next prime is 7500525727. The reversal of 7500525721 is 1275250057.

It can be written as a sum of positive squares in 3 ways, for example, as 337273225 + 7163252496 = 18365^2 + 84636^2 .

It is not a de Polignac number, because 7500525721 - 2³ = 7500525713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7500525727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22190736 + ... + 22191073.

It is an arithmetic number, because the mean of its divisors is an integer number (1353645205).

Almost surely, 2^7500525721 is an apocalyptic number.

It is an amenable number.

7500525721 is a deficient number, since it is larger than the sum of its proper divisors (621345509).

7500525721 is a wasteful number, since it uses less digits than its factorization.

7500525721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44381835 (or 44381822 counting only the distinct ones).

The product of its (nonzero) digits is 24500, while the sum is 34.

The square root of 7500525721 is about 86605.5755768646. The cubic root of 7500525721 is about 1957.4795556965.

Adding to 7500525721 its reverse (1275250057), we get a palindrome (8775775778).

The spelling of 7500525721 in words is "seven billion, five hundred million, five hundred twenty-five thousand, seven hundred twenty-one".