261962204166 has 288 divisors, whose sum is σ = 666053388000. Its totient is φ = 77033908224.

The previous prime is 261962204027. The next prime is 261962204183. The reversal of 261962204166 is 661402269162.

261962204166 is a `hidden beast` number, since 2 + 6 + 1 + 9 + 6 + 220 + 416 + 6 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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, 259625070 + ... + 259626078.

It is an arithmetic number, because the mean of its divisors is an integer number (2312685375).

Almost surely, 2^261962204166 is an apocalyptic number.

261962204166 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 261962204166, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (333026694000).

261962204166 is an abundant number, since it is smaller than the sum of its proper divisors (404091183834).

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

261962204166 is a wasteful number, since it uses less digits than its factorization.

261962204166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1190 (or 1165 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The spelling of 261962204166 in words is "two hundred sixty-one billion, nine hundred sixty-two million, two hundred four thousand, one hundred sixty-six".