261553759 has 2 divisors, whose sum is σ = 261553760. Its totient is φ = 261553758.

The previous prime is 261553751. The next prime is 261553819. The reversal of 261553759 is 957355162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261553759 - 2³ = 261553751 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261553751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130776879 + 130776880.

It is an arithmetic number, because the mean of its divisors is an integer number (130776880).

Almost surely, 2^261553759 is an apocalyptic number.

261553759 is a deficient number, since it is larger than the sum of its proper divisors (1).

261553759 is an equidigital number, since it uses as much as digits as its factorization.

261553759 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 283500, while the sum is 43.

The square root of 261553759 is about 16172.6237512656. The cubic root of 261553759 is about 639.5192996837.

The spelling of 261553759 in words is "two hundred sixty-one million, five hundred fifty-three thousand, seven hundred fifty-nine".