105843781 has 4 divisors (see below), whose sum is σ = 106935052. Its totient is φ = 104752512.

The previous prime is 105843763. The next prime is 105843797. The reversal of 105843781 is 187348501.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 53787556 + 52056225 = 7334^2 + 7215^2 .

It is a cyclic number.

It is not a de Polignac number, because 105843781 - 2⁷ = 105843653 is a prime.

It is a super-2 number, since 2×105843781² = 22405811952751922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 105843781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105843721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 545490 + ... + 545683.

It is an arithmetic number, because the mean of its divisors is an integer number (26733763).

Almost surely, 2^105843781 is an apocalyptic number.

It is an amenable number.

105843781 is a deficient number, since it is larger than the sum of its proper divisors (1091271).

105843781 is an equidigital number, since it uses as much as digits as its factorization.

105843781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1091270.

The product of its (nonzero) digits is 26880, while the sum is 37.

The square root of 105843781 is about 10288.0406783799. The cubic root of 105843781 is about 473.0297424484.

It can be divided in two parts, 10584 and 3781, that added together give a triangular number (14365 = T₁₆₉).

The spelling of 105843781 in words is "one hundred five million, eight hundred forty-three thousand, seven hundred eighty-one".