2100121200 has 90 divisors (see below), whose sum is σ = 7288016424. Its totient is φ = 560031360.

The previous prime is 2100121189. The next prime is 2100121253. The reversal of 2100121200 is 21210012.

It is a tau number, because it is divible by the number of its divisors (90).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 288084 + ... + 295283.

Almost surely, 2^2100121200 is an apocalyptic number.

2100121200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2100121200 is an abundant number, since it is smaller than the sum of its proper divisors (5187895224).

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

2100121200 is a wasteful number, since it uses less digits than its factorization.

2100121200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 583391 (or 583377 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 2100121200 is about 45827.0793308934. The cubic root of 2100121200 is about 1280.6038004175.

Adding to 2100121200 its reverse (21210012), we get a palindrome (2121331212).

The spelling of 2100121200 in words is "two billion, one hundred million, one hundred twenty-one thousand, two hundred".