7506566621 has 2 divisors, whose sum is σ = 7506566622. Its totient is φ = 7506566620.

The previous prime is 7506566581. The next prime is 7506566629. The reversal of 7506566621 is 1266656057.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4811503225 + 2695063396 = 69365^2 + 51914^2 .

It is an emirp because it is prime and its reverse (1266656057) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7506566621 - 2¹⁴ = 7506550237 is a prime.

It is a super-2 number, since 2×7506566621² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7506566629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3753283310 + 3753283311.

It is an arithmetic number, because the mean of its divisors is an integer number (3753283311).

Almost surely, 2^7506566621 is an apocalyptic number.

It is an amenable number.

7506566621 is a deficient number, since it is larger than the sum of its proper divisors (1).

7506566621 is an equidigital number, since it uses as much as digits as its factorization.

7506566621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 453600, while the sum is 44.

The square root of 7506566621 is about 86640.4444875487. Note that the first 4 decimals coincide. The cubic root of 7506566621 is about 1958.0049306510.

The spelling of 7506566621 in words is "seven billion, five hundred six million, five hundred sixty-six thousand, six hundred twenty-one".