261661652 has 24 divisors (see below), whose sum is σ = 528220224. Its totient is φ = 111091392.

The previous prime is 261661649. The next prime is 261661721. The reversal of 261661652 is 256166162.

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, 40673 + ... + 46664.

It is an arithmetic number, because the mean of its divisors is an integer number (22009176).

Almost surely, 2^261661652 is an apocalyptic number.

It is an amenable number.

261661652 is an abundant number, since it is smaller than the sum of its proper divisors (266558572).

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

261661652 is a wasteful number, since it uses less digits than its factorization.

261661652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87455 (or 87453 counting only the distinct ones).

The product of its digits is 25920, while the sum is 35.

The square root of 261661652 is about 16175.9590751213. The cubic root of 261661652 is about 639.6072231895.

The spelling of 261661652 in words is "two hundred sixty-one million, six hundred sixty-one thousand, six hundred fifty-two".