261868775 has 12 divisors (see below), whose sum is σ = 371105712. Its totient is φ = 179567040.

The previous prime is 261868759. The next prime is 261868781. The reversal of 261868775 is 577868162.

It is not a de Polignac number, because 261868775 - 2⁴ = 261868759 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 748022 + ... + 748371.

It is an arithmetic number, because the mean of its divisors is an integer number (30925476).

Almost surely, 2^261868775 is an apocalyptic number.

261868775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

261868775 is a deficient number, since it is larger than the sum of its proper divisors (109236937).

261868775 is a wasteful number, since it uses less digits than its factorization.

261868775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1496410 (or 1496405 counting only the distinct ones).

The product of its digits is 1128960, while the sum is 50.

The square root of 261868775 is about 16182.3599947597. The cubic root of 261868775 is about 639.7759428908.

The spelling of 261868775 in words is "two hundred sixty-one million, eight hundred sixty-eight thousand, seven hundred seventy-five".