21267912 has 16 divisors (see below), whose sum is σ = 53169840. Its totient is φ = 7089296.

The previous prime is 21267899. The next prime is 21267913. The reversal of 21267912 is 21976212.

It is a self number, because there is not a number n which added to its sum of digits gives 21267912.

It is not an unprimeable number, because it can be changed into a prime (21267913) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 443058 + ... + 443105.

It is an arithmetic number, because the mean of its divisors is an integer number (3323115).

Almost surely, 2^21267912 is an apocalyptic number.

It is an amenable number.

21267912 is an abundant number, since it is smaller than the sum of its proper divisors (31901928).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21267912 is a wasteful number, since it uses less digits than its factorization.

21267912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 886172 (or 886168 counting only the distinct ones).

The product of its digits is 3024, while the sum is 30.

The square root of 21267912 is about 4611.7146485879. The cubic root of 21267912 is about 277.0607155764.

The spelling of 21267912 in words is "twenty-one million, two hundred sixty-seven thousand, nine hundred twelve".