2105213815 has 4 divisors (see below), whose sum is σ = 2526256584. Its totient is φ = 1684171048.

The previous prime is 2105213777. The next prime is 2105213833. The reversal of 2105213815 is 5183125012.

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 2105213815 - 2⁹ = 2105213303 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, 210521377 + ... + 210521386.

It is an arithmetic number, because the mean of its divisors is an integer number (631564146).

Almost surely, 2^2105213815 is an apocalyptic number.

2105213815 is a deficient number, since it is larger than the sum of its proper divisors (421042769).

2105213815 is an equidigital number, since it uses as much as digits as its factorization.

2105213815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 421042768.

The product of its (nonzero) digits is 2400, while the sum is 28.

The square root of 2105213815 is about 45882.6090692323. The cubic root of 2105213815 is about 1281.6380832252.

Adding to 2105213815 its reverse (5183125012), we get a palindrome (7288338827).

The spelling of 2105213815 in words is "two billion, one hundred five million, two hundred thirteen thousand, eight hundred fifteen".