261686260 has 24 divisors (see below), whose sum is σ = 599499936. Its totient is φ = 95158560.

The previous prime is 261686251. The next prime is 261686273. The reversal of 261686260 is 62686162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 594522 + ... + 594961.

It is an arithmetic number, because the mean of its divisors is an integer number (24979164).

Almost surely, 2^261686260 is an apocalyptic number.

261686260 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261686260 is an abundant number, since it is smaller than the sum of its proper divisors (337813676).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261686260 is a wasteful number, since it uses less digits than its factorization.

261686260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1189503 (or 1189501 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 37.

The square root of 261686260 is about 16176.7196921997. The cubic root of 261686260 is about 639.6272732058.

The spelling of 261686260 in words is "two hundred sixty-one million, six hundred eighty-six thousand, two hundred sixty".