21120343 has 16 divisors (see below), whose sum is σ = 23109120. Its totient is φ = 19236096.

The previous prime is 21120317. The next prime is 21120349. The reversal of 21120343 is 34302112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21120343 - 2⁵ = 21120311 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120349) 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, 59655 + ... + 60007.

It is an arithmetic number, because the mean of its divisors is an integer number (1444320).

Almost surely, 2^21120343 is an apocalyptic number.

21120343 is a deficient number, since it is larger than the sum of its proper divisors (1988777).

21120343 is a wasteful number, since it uses less digits than its factorization.

21120343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 486.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 21120343 is about 4595.6874349764. The cubic root of 21120343 is about 276.4184255782.

Adding to 21120343 its reverse (34302112), we get a palindrome (55422455).

The spelling of 21120343 in words is "twenty-one million, one hundred twenty thousand, three hundred forty-three".