2106856819 has 4 divisors (see below), whose sum is σ = 2217744040. Its totient is φ = 1995969600.

The previous prime is 2106856771. The next prime is 2106856837. The reversal of 2106856819 is 9186586012.

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

It is a cyclic number.

It is not a de Polignac number, because 2106856819 - 2¹⁹ = 2106332531 is a prime.

It is a super-2 number, since 2×2106856819² = 8877691311533597522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2106856859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55443582 + ... + 55443619.

It is an arithmetic number, because the mean of its divisors is an integer number (554436010).

Almost surely, 2^2106856819 is an apocalyptic number.

2106856819 is a deficient number, since it is larger than the sum of its proper divisors (110887221).

2106856819 is a wasteful number, since it uses less digits than its factorization.

2106856819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110887220.

The product of its (nonzero) digits is 207360, while the sum is 46.

The square root of 2106856819 is about 45900.5100080598. The cubic root of 2106856819 is about 1281.9714126184.

The spelling of 2106856819 in words is "two billion, one hundred six million, eight hundred fifty-six thousand, eight hundred nineteen".