21214554 has 16 divisors (see below), whose sum is σ = 42569280. Its totient is φ = 7048160.

The previous prime is 21214553. The next prime is 21214577. The reversal of 21214554 is 45541212.

It is not an unprimeable number, because it can be changed into a prime (21214553) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 3819 + ... + 7550.

It is an arithmetic number, because the mean of its divisors is an integer number (2660580).

Almost surely, 2^21214554 is an apocalyptic number.

21214554 is an abundant number, since it is smaller than the sum of its proper divisors (21354726).

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

21214554 is a wasteful number, since it uses less digits than its factorization.

21214554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11685.

The product of its digits is 1600, while the sum is 24.

The square root of 21214554 is about 4605.9259655361. The cubic root of 21214554 is about 276.8288202837.

Adding to 21214554 its reverse (45541212), we get a palindrome (66755766).

The spelling of 21214554 in words is "twenty-one million, two hundred fourteen thousand, five hundred fifty-four".