261031233600 has 252 divisors, whose sum is σ = 928612709700. Its totient is φ = 69544857600.

The previous prime is 261031233583. The next prime is 261031233607. The reversal of 261031233600 is 6332130162.

It is a happy number.

261031233600 is a `hidden beast` number, since 2 + 6 + 1 + 0 + 31 + 23 + 3 + 600 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 98247744 + 260932985856 = 9912^2 + 510816^2 .

It is not an unprimeable number, because it can be changed into a prime (261031233607) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 16998726 + ... + 17014074.

Almost surely, 2^261031233600 is an apocalyptic number.

261031233600 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 261031233600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (464306354850).

261031233600 is an abundant number, since it is smaller than the sum of its proper divisors (667581476100).

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

261031233600 is a wasteful number, since it uses less digits than its factorization.

261031233600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16558 (or 16540 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 27.

Adding to 261031233600 its reverse (6332130162), we get a palindrome (267363363762).

The spelling of 261031233600 in words is "two hundred sixty-one billion, thirty-one million, two hundred thirty-three thousand, six hundred".