2102813 has 4 divisors (see below), whose sum is σ = 2118300. Its totient is φ = 2087328.

The previous prime is 2102809. The next prime is 2102831. The reversal of 2102813 is 3182012.

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 964324 + 1138489 = 982^2 + 1067^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102813 - 2² = 2102809 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2102791 and 2102800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2102873) 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, 7538 + ... + 7811.

It is an arithmetic number, because the mean of its divisors is an integer number (529575).

2^2102813 is an apocalyptic number.

It is an amenable number.

2102813 is a deficient number, since it is larger than the sum of its proper divisors (15487).

2102813 is a wasteful number, since it uses less digits than its factorization.

2102813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15486.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 2102813 is about 1450.1079270178. The cubic root of 2102813 is about 128.1150698630.

Adding to 2102813 its reverse (3182012), we get a palindrome (5284825).

The spelling of 2102813 in words is "two million, one hundred two thousand, eight hundred thirteen".