21021222200 has 96 divisors (see below), whose sum is σ = 54191866320. Its totient is φ = 7518720000.

The previous prime is 21021222179. The next prime is 21021222221. The reversal of 21021222200 is 222212012.

It is an interprime number because it is at equal distance from previous prime (21021222179) and next prime (21021222221).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55880 + ... + 212520.

Almost surely, 2^21021222200 is an apocalyptic number.

21021222200 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 21021222200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27095933160).

21021222200 is an abundant number, since it is smaller than the sum of its proper divisors (33170644120).

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

21021222200 is a wasteful number, since it uses less digits than its factorization.

21021222200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156729 (or 156720 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21021222200 its reverse (222212012), we get a palindrome (21243434212).

The spelling of 21021222200 in words is "twenty-one billion, twenty-one million, two hundred twenty-two thousand, two hundred".