21554116 has 12 divisors (see below), whose sum is σ = 38359440. Its totient is φ = 10594280.

The previous prime is 21554111. The next prime is 21554149. The reversal of 21554116 is 61145512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21554111) 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 3 ways as a sum of consecutive naturals, for example, 45430 + ... + 45901.

It is an arithmetic number, because the mean of its divisors is an integer number (3196620).

Almost surely, 2^21554116 is an apocalyptic number.

It is an amenable number.

21554116 is a deficient number, since it is larger than the sum of its proper divisors (16805324).

21554116 is a wasteful number, since it uses less digits than its factorization.

21554116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91394 (or 91392 counting only the distinct ones).

The product of its digits is 1200, while the sum is 25.

The square root of 21554116 is about 4642.6410587079. The cubic root of 21554116 is about 278.2979914568.

Adding to 21554116 its reverse (61145512), we get a palindrome (82699628).

The spelling of 21554116 in words is "twenty-one million, five hundred fifty-four thousand, one hundred sixteen".