212121120100 has 18 divisors (see below), whose sum is σ = 460302830834. Its totient is φ = 84848448000.

The previous prime is 212121120083. The next prime is 212121120103. The reversal of 212121120100 is 1021121212.

It can be written as a sum of positive squares in 3 ways, for example, as 4234365184 + 207886754916 = 65072^2 + 455946^2 .

It is not an unprimeable number, because it can be changed into a prime (212121120103) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1060605501 + ... + 1060605700.

Almost surely, 2^212121120100 is an apocalyptic number.

212121120100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212121120100 is an abundant number, since it is smaller than the sum of its proper divisors (248181710734).

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

212121120100 is a wasteful number, since it uses less digits than its factorization.

212121120100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2121211215 (or 2121211208 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 212121120100 its reverse (1021121212), we get a palindrome (213142241312).

The spelling of 212121120100 in words is "two hundred twelve billion, one hundred twenty-one million, one hundred twenty thousand, one hundred".