2106903805 has 4 divisors (see below), whose sum is σ = 2528284572. Its totient is φ = 1685523040.

The previous prime is 2106903791. The next prime is 2106903811. The reversal of 2106903805 is 5083096012.

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 282845124 + 1824058681 = 16818^2 + 42709^2 .

It is not a de Polignac number, because 2106903805 - 2¹⁵ = 2106871037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 210690376 + ... + 210690385.

It is an arithmetic number, because the mean of its divisors is an integer number (632071143).

Almost surely, 2^2106903805 is an apocalyptic number.

It is an amenable number.

2106903805 is a deficient number, since it is larger than the sum of its proper divisors (421380767).

2106903805 is an equidigital number, since it uses as much as digits as its factorization.

2106903805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 421380766.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 2106903805 is about 45901.0218295846. The cubic root of 2106903805 is about 1281.9809424958.

Adding to 2106903805 its reverse (5083096012), we get a palindrome (7189999817).

The spelling of 2106903805 in words is "two billion, one hundred six million, nine hundred three thousand, eight hundred five".