21707105 has 16 divisors (see below), whose sum is σ = 29890560. Its totient is φ = 14824512.

The previous prime is 21707089. The next prime is 21707117. The reversal of 21707105 is 50170712.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21707105 - 2⁴ = 21707089 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, 8576 + ... + 10814.

It is an arithmetic number, because the mean of its divisors is an integer number (1868160).

Almost surely, 2^21707105 is an apocalyptic number.

It is an amenable number.

21707105 is a deficient number, since it is larger than the sum of its proper divisors (8183455).

21707105 is a wasteful number, since it uses less digits than its factorization.

21707105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2528.

The product of its (nonzero) digits is 490, while the sum is 23.

The square root of 21707105 is about 4659.0884301546. The cubic root of 21707105 is about 278.9548836577.

Adding to 21707105 its reverse (50170712), we get a palindrome (71877817).

It can be divided in two parts, 21707 and 105, that added together give a palindrome (21812).

The spelling of 21707105 in words is "twenty-one million, seven hundred seven thousand, one hundred five".