21268908 has 36 divisors (see below), whose sum is σ = 54054000. Its totient is φ = 7051296.

The previous prime is 21268903. The next prime is 21268909. The reversal of 21268908 is 80986212.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a plaindrome in base 16.

It is a zygodrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (21268901) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5593 + ... + 8591.

It is an arithmetic number, because the mean of its divisors is an integer number (1501500).

Almost surely, 2^21268908 is an apocalyptic number.

It is an amenable number.

21268908 is an abundant number, since it is smaller than the sum of its proper divisors (32785092).

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

21268908 is a wasteful number, since it uses less digits than its factorization.

21268908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3206 (or 3201 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 21268908 is about 4611.8226331896. The cubic root of 21268908 is about 277.0650405295.

The spelling of 21268908 in words is "twenty-one million, two hundred sixty-eight thousand, nine hundred eight".