21144306 has 32 divisors (see below), whose sum is σ = 44115840. Its totient is φ = 6747776.

The previous prime is 21144301. The next prime is 21144307. The reversal of 21144306 is 60344112.

It is not an unprimeable number, because it can be changed into a prime (21144301) 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 15 ways as a sum of consecutive naturals, for example, 23395 + ... + 24281.

It is an arithmetic number, because the mean of its divisors is an integer number (1378620).

Almost surely, 2^21144306 is an apocalyptic number.

21144306 is an abundant number, since it is smaller than the sum of its proper divisors (22971534).

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

21144306 is a wasteful number, since it uses less digits than its factorization.

21144306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1058.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 21144306 is about 4598.2938140141. The cubic root of 21144306 is about 276.5229268987.

Adding to 21144306 its reverse (60344112), we get a palindrome (81488418).

The spelling of 21144306 in words is "twenty-one million, one hundred forty-four thousand, three hundred six".