265643325064561 has 2 divisors, whose sum is σ = 265643325064562. Its totient is φ = 265643325064560.

The previous prime is 265643325064547. The next prime is 265643325064573. The reversal of 265643325064561 is 165460523346562.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 172226383485025 + 93416941579536 = 13123505^2 + 9665244^2 .

It is a cyclic number.

It is not a de Polignac number, because 265643325064561 - 2²⁷ = 265643190846833 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 265643325064496 and 265643325064505.

It is not a weakly prime, because it can be changed into another prime (265643325062561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132821662532280 + 132821662532281.

It is an arithmetic number, because the mean of its divisors is an integer number (132821662532281).

Almost surely, 2^{265643325064561} is an apocalyptic number.

It is an amenable number.

265643325064561 is a deficient number, since it is larger than the sum of its proper divisors (1).

265643325064561 is an equidigital number, since it uses as much as digits as its factorization.

265643325064561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312000, while the sum is 58.

The spelling of 265643325064561 in words is "two hundred sixty-five trillion, six hundred forty-three billion, three hundred twenty-five million, sixty-four thousand, five hundred sixty-one".