21101220102 has 32 divisors (see below), whose sum is σ = 43383416832. Its totient is φ = 6837264864.

The previous prime is 21101220083. The next prime is 21101220103. The reversal of 21101220102 is 20102210112.

It is a super-2 number, since 2×21101220102² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101220103) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 197593 + ... + 285035.

It is an arithmetic number, because the mean of its divisors is an integer number (1355731776).

Almost surely, 2^21101220102 is an apocalyptic number.

21101220102 is an abundant number, since it is smaller than the sum of its proper divisors (22282196730).

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

21101220102 is a wasteful number, since it uses less digits than its factorization.

21101220102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88572.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21101220102 its reverse (20102210112), we get a palindrome (41203430214).

The spelling of 21101220102 in words is "twenty-one billion, one hundred one million, two hundred twenty thousand, one hundred two".