21111404 has 6 divisors (see below), whose sum is σ = 36944964. Its totient is φ = 10555700.

The previous prime is 21111397. The next prime is 21111457. The reversal of 21111404 is 40411112.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2638922 + ... + 2638929.

It is an arithmetic number, because the mean of its divisors is an integer number (6157494).

Almost surely, 2^21111404 is an apocalyptic number.

It is an amenable number.

21111404 is a deficient number, since it is larger than the sum of its proper divisors (15833560).

21111404 is a wasteful number, since it uses less digits than its factorization.

21111404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5277855 (or 5277853 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 21111404 is about 4594.7147898428. The cubic root of 21111404 is about 276.3794228501.

Adding to 21111404 its reverse (40411112), we get a palindrome (61522516).

The spelling of 21111404 in words is "twenty-one million, one hundred eleven thousand, four hundred four".