21212200220100 has 108 divisors (see below), whose sum is σ = 61603033184784. Its totient is φ = 5635552754560.

The previous prime is 21212200220093. The next prime is 21212200220173. The reversal of 21212200220100 is 102200221212.

It is a super-2 number, since 2×21212200220100² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21212200220100.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 21219727 + ... + 22196873.

Almost surely, 2^{21212200220100} is an apocalyptic number.

21212200220100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21212200220100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30801516592392).

21212200220100 is an abundant number, since it is smaller than the sum of its proper divisors (40390832964684).

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

21212200220100 is a wasteful number, since it uses less digits than its factorization.

21212200220100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 977702 (or 977426 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21212200220100 its reverse (102200221212), we get a palindrome (21314400441312).

The spelling of 21212200220100 in words is "twenty-one trillion, two hundred twelve billion, two hundred million, two hundred twenty thousand, one hundred".