261589916 has 24 divisors (see below), whose sum is σ = 523676160. Its totient is φ = 112003632.

The previous prime is 261589903. The next prime is 261589943. The reversal of 261589916 is 619985162.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30425 + ... + 38063.

It is an arithmetic number, because the mean of its divisors is an integer number (21819840).

Almost surely, 2^261589916 is an apocalyptic number.

It is an amenable number.

261589916 is an abundant number, since it is smaller than the sum of its proper divisors (262086244).

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

261589916 is a wasteful number, since it uses less digits than its factorization.

261589916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8873 (or 8871 counting only the distinct ones).

The product of its digits is 233280, while the sum is 47.

The square root of 261589916 is about 16173.7415584644. The cubic root of 261589916 is about 639.5487672190.

The spelling of 261589916 in words is "two hundred sixty-one million, five hundred eighty-nine thousand, nine hundred sixteen".