21711105 has 64 divisors (see below), whose sum is σ = 42336000. Its totient is φ = 10492416.

The previous prime is 21711101. The next prime is 21711127. The reversal of 21711105 is 50111712.

It is a happy number.

It is not a de Polignac number, because 21711105 - 2² = 21711101 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21711101) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 156126 + ... + 156264.

It is an arithmetic number, because the mean of its divisors is an integer number (661500).

Almost surely, 2^21711105 is an apocalyptic number.

It is an amenable number.

21711105 is a deficient number, since it is larger than the sum of its proper divisors (20624895).

21711105 is a wasteful number, since it uses less digits than its factorization.

21711105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255 (or 249 counting only the distinct ones).

The product of its (nonzero) digits is 70, while the sum is 18.

The square root of 21711105 is about 4659.5176789020. The cubic root of 21711105 is about 278.9720170802.

Adding to 21711105 its reverse (50111712), we get a palindrome (71822817).

The spelling of 21711105 in words is "twenty-one million, seven hundred eleven thousand, one hundred five".