21726265 has 8 divisors (see below), whose sum is σ = 28441728. Its totient is φ = 15800880.

The previous prime is 21726251. The next prime is 21726311. The reversal of 21726265 is 56262712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21726265 - 2⁵ = 21726233 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 197457 + ... + 197566.

It is an arithmetic number, because the mean of its divisors is an integer number (3555216).

Almost surely, 2^21726265 is an apocalyptic number.

It is an amenable number.

21726265 is a deficient number, since it is larger than the sum of its proper divisors (6715463).

21726265 is a wasteful number, since it uses less digits than its factorization.

21726265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395039.

The product of its digits is 10080, while the sum is 31.

The square root of 21726265 is about 4661.1441728400. The cubic root of 21726265 is about 279.0369336562.

Adding to 21726265 its reverse (56262712), we get a palindrome (77988977).

The spelling of 21726265 in words is "twenty-one million, seven hundred twenty-six thousand, two hundred sixty-five".