21121221102 has 16 divisors (see below), whose sum is σ = 42872927232. Its totient is φ = 6935326200.

The previous prime is 21121221083. The next prime is 21121221113. The reversal of 21121221102 is 20112212112.

It is a super-2 number, since 2×21121221102² (a number of 21 digits) contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 26269774 + ... + 26270577.

It is an arithmetic number, because the mean of its divisors is an integer number (2679557952).

Almost surely, 2^21121221102 is an apocalyptic number.

21121221102 is an abundant number, since it is smaller than the sum of its proper divisors (21751706130).

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

21121221102 is a wasteful number, since it uses less digits than its factorization.

21121221102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52540423.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21121221102 its reverse (20112212112), we get a palindrome (41233433214).

The spelling of 21121221102 in words is "twenty-one billion, one hundred twenty-one million, two hundred twenty-one thousand, one hundred two".