261000100 has 36 divisors (see below), whose sum is σ = 568519168. Its totient is φ = 104004000.

The previous prime is 261000023. The next prime is 261000127. The reversal of 261000100 is 1000162.

It is a super-3 number, since 3×261000100³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22285 + ... + 31915.

Almost surely, 2^261000100 is an apocalyptic number.

261000100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261000100 is an abundant number, since it is smaller than the sum of its proper divisors (307519068).

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

261000100 is a wasteful number, since it uses less digits than its factorization.

261000100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9916 (or 9909 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 261000100 is about 16155.4975163255. The cubic root of 261000100 is about 639.0677344578.

Adding to 261000100 its reverse (1000162), we get a palindrome (262000262).

The spelling of 261000100 in words is "two hundred sixty-one million, one hundred", and thus it is an aban number.