21221021105 has 8 divisors (see below), whose sum is σ = 25482545664. Its totient is φ = 16965270000.

The previous prime is 21221021021. The next prime is 21221021113. The reversal of 21221021105 is 50112012212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21221021105 - 2¹² = 21221017009 is a prime.

It is a Duffinian number.

It is a Curzon 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 7 ways as a sum of consecutive naturals, for example, 1435271 + ... + 1449980.

It is an arithmetic number, because the mean of its divisors is an integer number (3185318208).

Almost surely, 2^21221021105 is an apocalyptic number.

It is an amenable number.

21221021105 is a deficient number, since it is larger than the sum of its proper divisors (4261524559).

21221021105 is a wasteful number, since it uses less digits than its factorization.

21221021105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2886727.

The product of its (nonzero) digits is 80, while the sum is 17.

Adding to 21221021105 its reverse (50112012212), we get a palindrome (71333033317).

The spelling of 21221021105 in words is "twenty-one billion, two hundred twenty-one million, twenty-one thousand, one hundred five".