261686495 has 16 divisors (see below), whose sum is σ = 361041408. Its totient is φ = 178363680.

The previous prime is 261686489. The next prime is 261686507. The reversal of 261686495 is 594686162.

It is not a de Polignac number, because 261686495 - 2⁶ = 261686431 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16541 + ... + 28230.

It is an arithmetic number, because the mean of its divisors is an integer number (22565088).

Almost surely, 2^261686495 is an apocalyptic number.

261686495 is a deficient number, since it is larger than the sum of its proper divisors (99354913).

261686495 is a wasteful number, since it uses less digits than its factorization.

261686495 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44950.

The product of its digits is 622080, while the sum is 47.

The square root of 261686495 is about 16176.7269557225. The cubic root of 261686495 is about 639.6274646722.

The spelling of 261686495 in words is "two hundred sixty-one million, six hundred eighty-six thousand, four hundred ninety-five".