2101819 has 4 divisors (see below), whose sum is σ = 2117080. Its totient is φ = 2086560.

The previous prime is 2101817. The next prime is 2101823. The reversal of 2101819 is 9181012.

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 2101819 - 2¹ = 2101817 is a prime.

It is a super-2 number, since 2×2101819² = 8835286217522, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

2101819 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 2101819.

It is not an unprimeable number, because it can be changed into a prime (2101811) 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, 7422 + ... + 7699.

It is an arithmetic number, because the mean of its divisors is an integer number (529270).

2^2101819 is an apocalyptic number.

2101819 is a deficient number, since it is larger than the sum of its proper divisors (15261).

2101819 is a wasteful number, since it uses less digits than its factorization.

2101819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15260.

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 2101819 is about 1449.7651533955. The cubic root of 2101819 is about 128.0948800109.

The spelling of 2101819 in words is "two million, one hundred one thousand, eight hundred nineteen".