261250266089 has 2 divisors, whose sum is σ = 261250266090. Its totient is φ = 261250266088.

The previous prime is 261250266023. The next prime is 261250266103. The reversal of 261250266089 is 980662052162.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 258058920025 + 3191346064 = 507995^2 + 56492^2 .

It is a cyclic number.

It is not a de Polignac number, because 261250266089 - 2³² = 256955298793 is a prime.

It is not a weakly prime, because it can be changed into another prime (261250263089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130625133044 + 130625133045.

It is an arithmetic number, because the mean of its divisors is an integer number (130625133045).

Almost surely, 2^261250266089 is an apocalyptic number.

It is an amenable number.

261250266089 is a deficient number, since it is larger than the sum of its proper divisors (1).

261250266089 is an equidigital number, since it uses as much as digits as its factorization.

261250266089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 622080, while the sum is 47.

The spelling of 261250266089 in words is "two hundred sixty-one billion, two hundred fifty million, two hundred sixty-six thousand, eighty-nine".