21011221110 has 64 divisors (see below), whose sum is σ = 55040705280. Its totient is φ = 5090897280.

The previous prime is 21011221097. The next prime is 21011221129. The reversal of 21011221110 is 1112211012.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 636984 + ... + 669156.

It is an arithmetic number, because the mean of its divisors is an integer number (860011020).

Almost surely, 2^21011221110 is an apocalyptic number.

21011221110 is an abundant number, since it is smaller than the sum of its proper divisors (34029484170).

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

21011221110 is a wasteful number, since it uses less digits than its factorization.

21011221110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34173.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21011221110 its reverse (1112211012), we get a palindrome (22123432122).

The spelling of 21011221110 in words is "twenty-one billion, eleven million, two hundred twenty-one thousand, one hundred ten".