105661881 has 32 divisors (see below), whose sum is σ = 171131520. Its totient is φ = 64037952.

The previous prime is 105661873. The next prime is 105661909. The reversal of 105661881 is 188166501.

105661881 is a `hidden beast` number, since 1 + 0 + 566 + 18 + 81 = 666.

It is not a de Polignac number, because 105661881 - 2³ = 105661873 is a prime.

It is a super-2 number, since 2×105661881² = 22328866192916322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (105661811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21271 + ... + 25763.

It is an arithmetic number, because the mean of its divisors is an integer number (5347860).

Almost surely, 2^105661881 is an apocalyptic number.

It is an amenable number.

105661881 is a deficient number, since it is larger than the sum of its proper divisors (65469639).

105661881 is a wasteful number, since it uses less digits than its factorization.

105661881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4582 (or 4576 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 105661881 is about 10279.1965152924. The cubic root of 105661881 is about 472.7586087474.

The spelling of 105661881 in words is "one hundred five million, six hundred sixty-one thousand, eight hundred eighty-one".