202121212100 has 72 divisors (see below), whose sum is σ = 452865348096. Its totient is φ = 78220800000.

The previous prime is 202121212091. The next prime is 202121212121. The reversal of 202121212100 is 1212121202.

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, 21047300 + ... + 21056900.

Almost surely, 2^202121212100 is an apocalyptic number.

202121212100 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 202121212100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (226432674048).

202121212100 is an abundant number, since it is smaller than the sum of its proper divisors (250744135996).

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

202121212100 is a wasteful number, since it uses less digits than its factorization.

202121212100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16437 (or 16430 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 202121212100 its reverse (1212121202), we get a palindrome (203333333302).

The spelling of 202121212100 in words is "two hundred two billion, one hundred twenty-one million, two hundred twelve thousand, one hundred".