21850066 has 16 divisors (see below), whose sum is σ = 39661056. Its totient is φ = 8813376.

The previous prime is 21850061. The next prime is 21850093. The reversal of 21850066 is 66005812.

It is not an unprimeable number, because it can be changed into a prime (21850061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45666 + ... + 46141.

It is an arithmetic number, because the mean of its divisors is an integer number (2478816).

Almost surely, 2^21850066 is an apocalyptic number.

21850066 is a deficient number, since it is larger than the sum of its proper divisors (17810990).

21850066 is a wasteful number, since it uses less digits than its factorization.

21850066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91833.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 21850066 is about 4674.4054167348. The cubic root of 21850066 is about 279.5659345878.

Adding to 21850066 its reverse (66005812), we get a palindrome (87855878).

The spelling of 21850066 in words is "twenty-one million, eight hundred fifty thousand, sixty-six".