21726105 has 16 divisors (see below), whose sum is σ = 35610624. Its totient is φ = 11304320.

The previous prime is 21726073. The next prime is 21726113. The reversal of 21726105 is 50162712.

It is not a de Polignac number, because 21726105 - 2⁵ = 21726073 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, 17049 + ... + 18278.

It is an arithmetic number, because the mean of its divisors is an integer number (2225664).

Almost surely, 2^21726105 is an apocalyptic number.

It is an amenable number.

21726105 is a deficient number, since it is larger than the sum of its proper divisors (13884519).

21726105 is a wasteful number, since it uses less digits than its factorization.

21726105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35376.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 21726105 is about 4661.1270096405. The cubic root of 21726105 is about 279.0362486786.

Adding to 21726105 its reverse (50162712), we get a palindrome (71888817).

The spelling of 21726105 in words is "twenty-one million, seven hundred twenty-six thousand, one hundred five".