105728661 has 12 divisors (see below), whose sum is σ = 161702892. Its totient is φ = 66339456.

The previous prime is 105728657. The next prime is 105728669. The reversal of 105728661 is 166827501.

105728661 is a `hidden beast` number, since 1 + 0 + 572 + 86 + 6 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 51926436 + 53802225 = 7206^2 + 7335^2 .

It is not a de Polignac number, because 105728661 - 2² = 105728657 is a prime.

It is a super-2 number, since 2×105728661² = 22357099513705842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105728669) 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 11 ways as a sum of consecutive naturals, for example, 345366 + ... + 345671.

It is an arithmetic number, because the mean of its divisors is an integer number (13475241).

Almost surely, 2^105728661 is an apocalyptic number.

It is an amenable number.

105728661 is a deficient number, since it is larger than the sum of its proper divisors (55974231).

105728661 is a wasteful number, since it uses less digits than its factorization.

105728661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 691060 (or 691057 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 105728661 is about 10282.4443105713. Note that the first 3 decimals coincide. The cubic root of 105728661 is about 472.8581847750.

The spelling of 105728661 in words is "one hundred five million, seven hundred twenty-eight thousand, six hundred sixty-one".