261323369 has 2 divisors, whose sum is σ = 261323370. Its totient is φ = 261323368.

The previous prime is 261323347. The next prime is 261323399. The reversal of 261323369 is 963323162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 209670400 + 51652969 = 14480^2 + 7187^2 .

It is a cyclic number.

It is not a de Polignac number, because 261323369 - 2⁸ = 261323113 is a prime.

It is a super-2 number, since 2×261323369² = 136579806371020322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (261323339) 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, 130661684 + 130661685.

It is an arithmetic number, because the mean of its divisors is an integer number (130661685).

Almost surely, 2^261323369 is an apocalyptic number.

It is an amenable number.

261323369 is a deficient number, since it is larger than the sum of its proper divisors (1).

261323369 is an equidigital number, since it uses as much as digits as its factorization.

261323369 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992, while the sum is 35.

The square root of 261323369 is about 16165.4993427361. The cubic root of 261323369 is about 639.3314706953.

The spelling of 261323369 in words is "two hundred sixty-one million, three hundred twenty-three thousand, three hundred sixty-nine".