261500 has 24 divisors (see below), whose sum is σ = 572208. Its totient is φ = 104400.

The previous prime is 261467. The next prime is 261509. The reversal of 261500 is 5162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261509) 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, 239 + ... + 761.

It is an arithmetic number, because the mean of its divisors is an integer number (23842).

2²⁶¹⁵⁰⁰ is an apocalyptic number.

261500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (286104).

261500 is an abundant number, since it is smaller than the sum of its proper divisors (310708).

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

261500 is a wasteful number, since it uses less digits than its factorization.

261500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 542 (or 530 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 261500 is about 511.3707070218. The cubic root of 261500 is about 63.9475481702.

Adding to 261500 its reverse (5162), we get a palindrome (266662).

The spelling of 261500 in words is "two hundred sixty-one thousand, five hundred".