2021805105 has 32 divisors (see below), whose sum is σ = 3409449600. Its totient is φ = 1020252672.

The previous prime is 2021805083. The next prime is 2021805109. The reversal of 2021805105 is 5015081202.

It is a de Polignac number, because none of the positive numbers 2^k-2021805105 is a prime.

It is a super-2 number, since 2×2021805105² = 8175391765208122050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2021805109) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 245901 + ... + 253989.

It is an arithmetic number, because the mean of its divisors is an integer number (106545300).

Almost surely, 2^2021805105 is an apocalyptic number.

It is an amenable number.

2021805105 is a deficient number, since it is larger than the sum of its proper divisors (1387644495).

2021805105 is a wasteful number, since it uses less digits than its factorization.

2021805105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8993.

The product of its (nonzero) digits is 800, while the sum is 24.

The square root of 2021805105 is about 44964.4871537528. The cubic root of 2021805105 is about 1264.4832949394.

Adding to 2021805105 its reverse (5015081202), we get a palindrome (7036886307).

The spelling of 2021805105 in words is "two billion, twenty-one million, eight hundred five thousand, one hundred five".