21113230221 has 6 divisors (see below), whose sum is σ = 30496888110. Its totient is φ = 14075486808.

The previous prime is 21113230207. The next prime is 21113230289. The reversal of 21113230221 is 12203231112.

21113230221 is a `hidden beast` number, since 211 + 1 + 3 + 230 + 221 = 666.

It can be written as a sum of positive squares in only one way, i.e., 20253274596 + 859955625 = 142314^2 + 29325^2 .

It is not a de Polignac number, because 21113230221 - 2⁶ = 21113230157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21113230194 and 21113230203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113230321) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1172957226 + ... + 1172957243.

It is an arithmetic number, because the mean of its divisors is an integer number (5082814685).

Almost surely, 2^21113230221 is an apocalyptic number.

It is an amenable number.

21113230221 is a deficient number, since it is larger than the sum of its proper divisors (9383657889).

21113230221 is a wasteful number, since it uses less digits than its factorization.

21113230221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2345914475 (or 2345914472 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21113230221 its reverse (12203231112), we get a palindrome (33316461333).

The spelling of 21113230221 in words is "twenty-one billion, one hundred thirteen million, two hundred thirty thousand, two hundred twenty-one".