105815813 has 4 divisors (see below), whose sum is σ = 106011948. Its totient is φ = 105619680.

The previous prime is 105815789. The next prime is 105815821. The reversal of 105815813 is 318518501.

It is a happy number.

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 72199009 + 33616804 = 8497^2 + 5798^2 .

It is a cyclic number.

It is not a de Polignac number, because 105815813 - 2²⁰ = 104767237 is a prime.

It is a super-2 number, since 2×105815813² = 22393972561701938, 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 105815813.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105815833) 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, 97256 + ... + 98337.

It is an arithmetic number, because the mean of its divisors is an integer number (26502987).

Almost surely, 2^105815813 is an apocalyptic number.

It is an amenable number.

105815813 is a deficient number, since it is larger than the sum of its proper divisors (196135).

105815813 is an equidigital number, since it uses as much as digits as its factorization.

105815813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196134.

The product of its (nonzero) digits is 4800, while the sum is 32.

The square root of 105815813 is about 10286.6813404518. The cubic root of 105815813 is about 472.9880745578.

The spelling of 105815813 in words is "one hundred five million, eight hundred fifteen thousand, eight hundred thirteen".