21921096 has 64 divisors (see below), whose sum is σ = 56635200. Its totient is φ = 7067648.

The previous prime is 21921083. The next prime is 21921113. The reversal of 21921096 is 69012912.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 159940 + ... + 160076.

It is an arithmetic number, because the mean of its divisors is an integer number (884925).

Almost surely, 2^21921096 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21921096, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28317600).

21921096 is an abundant number, since it is smaller than the sum of its proper divisors (34714104).

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

21921096 is a wasteful number, since it uses less digits than its factorization.

21921096 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318 (or 314 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 21921096 is about 4681.9970098239. The cubic root of 21921096 is about 279.8685437349.

The spelling of 21921096 in words is "twenty-one million, nine hundred twenty-one thousand, ninety-six".