21111330 has 16 divisors (see below), whose sum is σ = 50667264. Its totient is φ = 5629680.

The previous prime is 21111301. The next prime is 21111373. The reversal of 21111330 is 3311112.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 351826 + ... + 351885.

It is an arithmetic number, because the mean of its divisors is an integer number (3166704).

Almost surely, 2^21111330 is an apocalyptic number.

21111330 is an abundant number, since it is smaller than the sum of its proper divisors (29555934).

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

21111330 is a wasteful number, since it uses less digits than its factorization.

21111330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 703721.

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 21111330 is about 4594.7067371052. The cubic root of 21111330 is about 276.3790999267.

Adding to 21111330 its reverse (3311112), we get a palindrome (24422442).

The spelling of 21111330 in words is "twenty-one million, one hundred eleven thousand, three hundred thirty".