266572661 has 2 divisors, whose sum is σ = 266572662. Its totient is φ = 266572660.

The previous prime is 266572651. The next prime is 266572667. The reversal of 266572661 is 166275662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 212255761 + 54316900 = 14569^2 + 7370^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-266572661 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (266572667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133286330 + 133286331.

It is an arithmetic number, because the mean of its divisors is an integer number (133286331).

Almost surely, 2^266572661 is an apocalyptic number.

It is an amenable number.

266572661 is a deficient number, since it is larger than the sum of its proper divisors (1).

266572661 is an equidigital number, since it uses as much as digits as its factorization.

266572661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 181440, while the sum is 41.

The square root of 266572661 is about 16327.0530408889. The cubic root of 266572661 is about 643.5839462867.

The spelling of 266572661 in words is "two hundred sixty-six million, five hundred seventy-two thousand, six hundred sixty-one".