21201105 has 16 divisors (see below), whose sum is σ = 34332480. Its totient is φ = 11170368.

The previous prime is 21201083. The next prime is 21201109. The reversal of 21201105 is 50110212.

It is not a de Polignac number, because 21201105 - 2⁶ = 21201041 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21201109) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7270 + ... + 9759.

It is an arithmetic number, because the mean of its divisors is an integer number (2145780).

Almost surely, 2^21201105 is an apocalyptic number.

It is an amenable number.

21201105 is a deficient number, since it is larger than the sum of its proper divisors (13131375).

21201105 is a wasteful number, since it uses less digits than its factorization.

21201105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17120.

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 21201105 is about 4604.4657670570. The cubic root of 21201105 is about 276.7703092283.

Adding to 21201105 its reverse (50110212), we get a palindrome (71311317).

The spelling of 21201105 in words is "twenty-one million, two hundred one thousand, one hundred five".