261099659 has 2 divisors, whose sum is σ = 261099660. Its totient is φ = 261099658.

The previous prime is 261099649. The next prime is 261099667. The reversal of 261099659 is 956990162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261099659 - 2⁸ = 261099403 is a prime.

It is not a weakly prime, because it can be changed into another prime (261099649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130549829 + 130549830.

It is an arithmetic number, because the mean of its divisors is an integer number (130549830).

Almost surely, 2^261099659 is an apocalyptic number.

261099659 is a deficient number, since it is larger than the sum of its proper divisors (1).

261099659 is an equidigital number, since it uses as much as digits as its factorization.

261099659 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 262440, while the sum is 47.

The square root of 261099659 is about 16158.5784956474. The cubic root of 261099659 is about 639.1489820082.

The spelling of 261099659 in words is "two hundred sixty-one million, ninety-nine thousand, six hundred fifty-nine".