261712660 has 24 divisors (see below), whose sum is σ = 599560416. Its totient is φ = 95168160.

The previous prime is 261712651. The next prime is 261712679. The reversal of 261712660 is 66217162.

It is a happy number.

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, 594582 + ... + 595021.

It is an arithmetic number, because the mean of its divisors is an integer number (24981684).

Almost surely, 2^261712660 is an apocalyptic number.

261712660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261712660 is an abundant number, since it is smaller than the sum of its proper divisors (337847756).

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

261712660 is a wasteful number, since it uses less digits than its factorization.

261712660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1189623 (or 1189621 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 261712660 is about 16177.5356590551. The cubic root of 261712660 is about 639.6487819038.

The spelling of 261712660 in words is "two hundred sixty-one million, seven hundred twelve thousand, six hundred sixty".