2105421305 has 16 divisors (see below), whose sum is σ = 2730989520. Its totient is φ = 1548979968.

The previous prime is 2105421281. The next prime is 2105421347. The reversal of 2105421305 is 5031245012.

It can be written as a sum of positive squares in 8 ways, for example, as 42354064 + 2063067241 = 6508^2 + 45421^2 .

It is a cyclic number.

It is not a de Polignac number, because 2105421305 - 2¹⁰ = 2105420281 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42722 + ... + 77691.

It is an arithmetic number, because the mean of its divisors is an integer number (170686845).

Almost surely, 2^2105421305 is an apocalyptic number.

It is an amenable number.

2105421305 is a deficient number, since it is larger than the sum of its proper divisors (625568215).

2105421305 is a wasteful number, since it uses less digits than its factorization.

2105421305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120700.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 2105421305 is about 45884.8701098739. The cubic root of 2105421305 is about 1281.6801879508.

Adding to 2105421305 its reverse (5031245012), we get a palindrome (7136666317).

The spelling of 2105421305 in words is "two billion, one hundred five million, four hundred twenty-one thousand, three hundred five".