261557200 has 30 divisors (see below), whose sum is σ = 628392134. Its totient is φ = 104622720.

The previous prime is 261557183. The next prime is 261557227. The reversal of 261557200 is 2755162.

It can be written as a sum of positive squares in 3 ways, for example, as 37994896 + 223562304 = 6164^2 + 14952^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 326547 + ... + 327346.

Almost surely, 2^261557200 is an apocalyptic number.

261557200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261557200 is an abundant number, since it is smaller than the sum of its proper divisors (366834934).

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

261557200 is a wasteful number, since it uses less digits than its factorization.

261557200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 653911 (or 653900 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 261557200 is about 16172.7301343960. The cubic root of 261557200 is about 639.5221041757.

The spelling of 261557200 in words is "two hundred sixty-one million, five hundred fifty-seven thousand, two hundred".