21328214 has 4 divisors (see below), whose sum is σ = 31992324. Its totient is φ = 10664106.

The previous prime is 21328213. The next prime is 21328247. The reversal of 21328214 is 41282312.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21328214.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21328213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5332052 + ... + 5332055.

It is an arithmetic number, because the mean of its divisors is an integer number (7998081).

Almost surely, 2^21328214 is an apocalyptic number.

21328214 is a deficient number, since it is larger than the sum of its proper divisors (10664110).

21328214 is a wasteful number, since it uses less digits than its factorization.

21328214 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10664109.

The product of its digits is 768, while the sum is 23.

The square root of 21328214 is about 4618.2479361767. The cubic root of 21328214 is about 277.3223232937.

The spelling of 21328214 in words is "twenty-one million, three hundred twenty-eight thousand, two hundred fourteen".