21221302111 has 4 divisors (see below), whose sum is σ = 21224155392. Its totient is φ = 21218448832.

The previous prime is 21221302087. The next prime is 21221302121. The reversal of 21221302111 is 11120312212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21221302111 - 2¹¹ = 21221300063 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221302121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1415455 + ... + 1430368.

It is an arithmetic number, because the mean of its divisors is an integer number (5306038848).

Almost surely, 2^21221302111 is an apocalyptic number.

21221302111 is a deficient number, since it is larger than the sum of its proper divisors (2853281).

21221302111 is an equidigital number, since it uses as much as digits as its factorization.

21221302111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2853280.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21221302111 its reverse (11120312212), we get a palindrome (32341614323).

The spelling of 21221302111 in words is "twenty-one billion, two hundred twenty-one million, three hundred two thousand, one hundred eleven".