21118650 has 48 divisors (see below), whose sum is σ = 59859264. Its totient is φ = 4826880.

The previous prime is 21118619. The next prime is 21118661. The reversal of 21118650 is 5681112.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21118650.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9007 + ... + 11106.

It is an arithmetic number, because the mean of its divisors is an integer number (1247068).

Almost surely, 2^21118650 is an apocalyptic number.

21118650 is an abundant number, since it is smaller than the sum of its proper divisors (38740614).

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

21118650 is a wasteful number, since it uses less digits than its factorization.

21118650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20135 (or 20130 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 24.

The square root of 21118650 is about 4595.5032368610. The cubic root of 21118650 is about 276.4110395097.

Adding to 21118650 its reverse (5681112), we get a palindrome (26799762).

The spelling of 21118650 in words is "twenty-one million, one hundred eighteen thousand, six hundred fifty".