261825840900 has 432 divisors, whose sum is σ = 911124684288. Its totient is φ = 62487936000.

The previous prime is 261825840889. The next prime is 261825840907. The reversal of 261825840900 is 9048528162.

261825840900 is a `hidden beast` number, since 2 + 61 + 8 + 2 + 584 + 0 + 9 + 0 + 0 = 666.

It is a super-2 number, since 2×261825840900² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (261825840907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 50670117 + ... + 50675283.

Almost surely, 2^261825840900 is an apocalyptic number.

261825840900 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 261825840900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (455562342144).

261825840900 is an abundant number, since it is smaller than the sum of its proper divisors (649298843388).

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

261825840900 is a wasteful number, since it uses less digits than its factorization.

261825840900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5332 (or 5322 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 261825840900 in words is "two hundred sixty-one billion, eight hundred twenty-five million, eight hundred forty thousand, nine hundred".