261152681 has 2 divisors, whose sum is σ = 261152682. Its totient is φ = 261152680.

The previous prime is 261152629. The next prime is 261152687. The reversal of 261152681 is 186251162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 235346281 + 25806400 = 15341^2 + 5080^2 .

It is a cyclic number.

It is not a de Polignac number, because 261152681 - 2¹⁴ = 261136297 is a prime.

It is a super-2 number, since 2×261152681² = 136401445586975522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (261152687) 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, 130576340 + 130576341.

It is an arithmetic number, because the mean of its divisors is an integer number (130576341).

Almost surely, 2^261152681 is an apocalyptic number.

It is an amenable number.

261152681 is a deficient number, since it is larger than the sum of its proper divisors (1).

261152681 is an equidigital number, since it uses as much as digits as its factorization.

261152681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 32.

The square root of 261152681 is about 16160.2190888614. The cubic root of 261152681 is about 639.1922434761.

The spelling of 261152681 in words is "two hundred sixty-one million, one hundred fifty-two thousand, six hundred eighty-one".