261866488 has 32 divisors (see below), whose sum is σ = 531468000. Its totient is φ = 120244608.

The previous prime is 261866461. The next prime is 261866489. The reversal of 261866488 is 884668162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261866489) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14370 + ... + 27022.

It is an arithmetic number, because the mean of its divisors is an integer number (16608375).

Almost surely, 2^261866488 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261866488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (265734000).

261866488 is an abundant number, since it is smaller than the sum of its proper divisors (269601512).

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

261866488 is a wasteful number, since it uses less digits than its factorization.

261866488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12871 (or 12867 counting only the distinct ones).

The product of its digits is 884736, while the sum is 49.

The square root of 261866488 is about 16182.2893312411. The cubic root of 261866488 is about 639.7740804162.

The spelling of 261866488 in words is "two hundred sixty-one million, eight hundred sixty-six thousand, four hundred eighty-eight".