2121102100 has 54 divisors (see below), whose sum is σ = 4984127610. Its totient is φ = 783169920.

The previous prime is 2121102091. The next prime is 2121102103. The reversal of 2121102100 is 12011212.

It can be written as a sum of positive squares in 9 ways, for example, as 710648964 + 1410453136 = 26658^2 + 37556^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121102103) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 45855 + ... + 79654.

Almost surely, 2^2121102100 is an apocalyptic number.

2121102100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2121102100 is an abundant number, since it is smaller than the sum of its proper divisors (2863025510).

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

2121102100 is a wasteful number, since it uses less digits than its factorization.

2121102100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125549 (or 125529 counting only the distinct ones).

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

The square root of 2121102100 is about 46055.4242190863. The cubic root of 2121102100 is about 1284.8542280401.

Adding to 2121102100 its reverse (12011212), we get a palindrome (2133113312).

The spelling of 2121102100 in words is "two billion, one hundred twenty-one million, one hundred two thousand, one hundred".