261936601800 has 384 divisors, whose sum is σ = 889464499200. Its totient is φ = 63479808000.

The previous prime is 261936601763. The next prime is 261936601847. The reversal of 261936601800 is 8106639162.

It is a super-2 number, since 2×261936601800² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 259599696 + ... + 259600704.

It is an arithmetic number, because the mean of its divisors is an integer number (2316313800).

Almost surely, 2^261936601800 is an apocalyptic number.

261936601800 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 261936601800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (444732249600).

261936601800 is an abundant number, since it is smaller than the sum of its proper divisors (627527897400).

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

261936601800 is a wasteful number, since it uses less digits than its factorization.

261936601800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1897 (or 1888 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 42.

The spelling of 261936601800 in words is "two hundred sixty-one billion, nine hundred thirty-six million, six hundred one thousand, eight hundred".