261455273 has 2 divisors, whose sum is σ = 261455274. Its totient is φ = 261455272.

The previous prime is 261455269. The next prime is 261455279. The reversal of 261455273 is 372554162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 184226329 + 77228944 = 13573^2 + 8788^2 .

It is a cyclic number.

It is not a de Polignac number, because 261455273 - 2² = 261455269 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (261455279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130727636 + 130727637.

It is an arithmetic number, because the mean of its divisors is an integer number (130727637).

Almost surely, 2^261455273 is an apocalyptic number.

It is an amenable number.

261455273 is a deficient number, since it is larger than the sum of its proper divisors (1).

261455273 is an equidigital number, since it uses as much as digits as its factorization.

261455273 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50400, while the sum is 35.

The square root of 261455273 is about 16169.5786277812. The cubic root of 261455273 is about 639.4390209614.

The spelling of 261455273 in words is "two hundred sixty-one million, four hundred fifty-five thousand, two hundred seventy-three".