21214368 has 144 divisors (see below), whose sum is σ = 73120320. Its totient is φ = 5695488.

The previous prime is 21214327. The next prime is 21214373. The reversal of 21214368 is 86341212.

It is a tau number, because it is divible by the number of its divisors (144).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33963 + ... + 34581.

It is an arithmetic number, because the mean of its divisors is an integer number (507780).

Almost surely, 2^21214368 is an apocalyptic number.

21214368 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21214368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36560160).

21214368 is an abundant number, since it is smaller than the sum of its proper divisors (51905952).

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

21214368 is a wasteful number, since it uses less digits than its factorization.

21214368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659 (or 648 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 21214368 is about 4605.9057741122. The cubic root of 21214368 is about 276.8280112430.

The spelling of 21214368 in words is "twenty-one million, two hundred fourteen thousand, three hundred sixty-eight".