7522566721 has 4 divisors (see below), whose sum is σ = 7523193600. Its totient is φ = 7521939844.

The previous prime is 7522566643. The next prime is 7522566769. The reversal of 7522566721 is 1276652257.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1276652257 = 7499 ⋅170243.

It is a cyclic number.

It is not a de Polignac number, because 7522566721 - 2¹³ = 7522558529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7522567721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 295081 + ... + 319558.

It is an arithmetic number, because the mean of its divisors is an integer number (1880798400).

Almost surely, 2^7522566721 is an apocalyptic number.

It is an amenable number.

7522566721 is a deficient number, since it is larger than the sum of its proper divisors (626879).

7522566721 is a wasteful number, since it uses less digits than its factorization.

7522566721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 626878.

The product of its digits is 352800, while the sum is 43.

The square root of 7522566721 is about 86732.7315435182. The cubic root of 7522566721 is about 1959.3950931606.

The spelling of 7522566721 in words is "seven billion, five hundred twenty-two million, five hundred sixty-six thousand, seven hundred twenty-one".