21002230221 has 16 divisors (see below), whose sum is σ = 32007001728. Its totient is φ = 11999923200.

The previous prime is 21002230217. The next prime is 21002230229. The reversal of 21002230221 is 12203220012.

It is a happy number.

It is not a de Polignac number, because 21002230221 - 2² = 21002230217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21002230221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002230229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 152701 + ... + 255581.

It is an arithmetic number, because the mean of its divisors is an integer number (2000437608).

Almost surely, 2^21002230221 is an apocalyptic number.

21002230221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21002230221 is a deficient number, since it is larger than the sum of its proper divisors (11004771507).

21002230221 is a wasteful number, since it uses less digits than its factorization.

21002230221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112612.

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 21002230221 its reverse (12203220012), we get a palindrome (33205450233).

The spelling of 21002230221 in words is "twenty-one billion, two million, two hundred thirty thousand, two hundred twenty-one".