261244500 has 192 divisors, whose sum is σ = 845365248. Its totient is φ = 62160000.

The previous prime is 261244481. The next prime is 261244513. The reversal of 261244500 is 5442162.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1171389 + ... + 1171611.

It is an arithmetic number, because the mean of its divisors is an integer number (4402944).

Almost surely, 2^261244500 is an apocalyptic number.

261244500 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 261244500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (422682624).

261244500 is an abundant number, since it is smaller than the sum of its proper divisors (584120748).

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

261244500 is a wasteful number, since it uses less digits than its factorization.

261244500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327 (or 315 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 261244500 is about 16163.0597350873. The cubic root of 261244500 is about 639.2671461671.

Adding to 261244500 its reverse (5442162), we get a palindrome (266686662).

The spelling of 261244500 in words is "two hundred sixty-one million, two hundred forty-four thousand, five hundred".