264220672561 has 2 divisors, whose sum is σ = 264220672562. Its totient is φ = 264220672560.

The previous prime is 264220672519. The next prime is 264220672589. The reversal of 264220672561 is 165276022462.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 245143814400 + 19076858161 = 495120^2 + 138119^2 .

It is a cyclic number.

It is not a de Polignac number, because 264220672561 - 2²⁹ = 263683801649 is a prime.

It is not a weakly prime, because it can be changed into another prime (264220672511) 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 as a sum of consecutive naturals, namely, 132110336280 + 132110336281.

It is an arithmetic number, because the mean of its divisors is an integer number (132110336281).

Almost surely, 2^264220672561 is an apocalyptic number.

It is an amenable number.

264220672561 is a deficient number, since it is larger than the sum of its proper divisors (1).

264220672561 is an equidigital number, since it uses as much as digits as its factorization.

264220672561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 483840, while the sum is 43.

The spelling of 264220672561 in words is "two hundred sixty-four billion, two hundred twenty million, six hundred seventy-two thousand, five hundred sixty-one".