2121012100 has 36 divisors (see below), whose sum is σ = 4626486004. Its totient is φ = 844001280.

The previous prime is 2121012097. The next prime is 2121012139. The reversal of 2121012100 is 12101212.

It can be written as a sum of positive squares in 6 ways, for example, as 363054916 + 1757957184 = 19054^2 + 41928^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35649 + ... + 74248.

Almost surely, 2^2121012100 is an apocalyptic number.

2121012100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2121012100 is an abundant number, since it is smaller than the sum of its proper divisors (2505473904).

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

2121012100 is a wasteful number, since it uses less digits than its factorization.

2121012100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110104 (or 110097 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 2121012100 is about 46054.4471251149. The cubic root of 2121012100 is about 1284.8360553307.

Adding to 2121012100 its reverse (12101212), we get a palindrome (2133113312).

The spelling of 2121012100 in words is "two billion, one hundred twenty-one million, twelve thousand, one hundred".