261356593 has 2 divisors, whose sum is σ = 261356594. Its totient is φ = 261356592.

The previous prime is 261356587. The next prime is 261356633. The reversal of 261356593 is 395653162.

It is a happy number.

It is an a-pointer prime, because the next prime (261356633) can be obtained adding 261356593 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 246741264 + 14615329 = 15708^2 + 3823^2 .

It is a cyclic number.

It is not a de Polignac number, because 261356593 - 2⁵ = 261356561 is a prime.

It is not a weakly prime, because it can be changed into another prime (261356573) 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, 130678296 + 130678297.

It is an arithmetic number, because the mean of its divisors is an integer number (130678297).

Almost surely, 2^261356593 is an apocalyptic number.

It is an amenable number.

261356593 is a deficient number, since it is larger than the sum of its proper divisors (1).

261356593 is an equidigital number, since it uses as much as digits as its factorization.

261356593 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145800, while the sum is 40.

The square root of 261356593 is about 16166.5269306676. The cubic root of 261356593 is about 639.3585638823.

The spelling of 261356593 in words is "two hundred sixty-one million, three hundred fifty-six thousand, five hundred ninety-three".