261644200 has 24 divisors (see below), whose sum is σ = 608323230. Its totient is φ = 104657600.

The previous prime is 261644167. The next prime is 261644203. The reversal of 261644200 is 2446162.

It can be written as a sum of positive squares in 3 ways, for example, as 150847524 + 110796676 = 12282^2 + 10526^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (261644203) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 653911 + ... + 654310.

Almost surely, 2^261644200 is an apocalyptic number.

261644200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261644200 is an abundant number, since it is smaller than the sum of its proper divisors (346679030).

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

261644200 is a wasteful number, since it uses less digits than its factorization.

261644200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1308237 (or 1308228 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 261644200 is about 16175.4196236141. The cubic root of 261644200 is about 639.5930029508.

The spelling of 261644200 in words is "two hundred sixty-one million, six hundred forty-four thousand, two hundred".