21330054 has 24 divisors (see below), whose sum is σ = 47927880. Its totient is φ = 7109856.

The previous prime is 21330047. The next prime is 21330059. The reversal of 21330054 is 45003312.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21330059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21459 + ... + 22430.

It is an arithmetic number, because the mean of its divisors is an integer number (1996995).

Almost surely, 2^21330054 is an apocalyptic number.

21330054 is an abundant number, since it is smaller than the sum of its proper divisors (26597826).

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

21330054 is an equidigital number, since it uses as much as digits as its factorization.

21330054 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43906 (or 43894 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 21330054 is about 4618.4471416267. The cubic root of 21330054 is about 277.3302979949.

Adding to 21330054 its reverse (45003312), we get a palindrome (66333366).

The spelling of 21330054 in words is "twenty-one million, three hundred thirty thousand, fifty-four".