2100203021 has 4 divisors (see below), whose sum is σ = 2400232032. Its totient is φ = 1800174012.

The previous prime is 2100203009. The next prime is 2100203023. The reversal of 2100203021 is 1203020012.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2100203021 - 2¹⁸ = 2099940877 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2100202993 and 2100203011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100203023) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 150014495 + ... + 150014508.

It is an arithmetic number, because the mean of its divisors is an integer number (600058008).

Almost surely, 2^2100203021 is an apocalyptic number.

It is an amenable number.

2100203021 is a deficient number, since it is larger than the sum of its proper divisors (300029011).

2100203021 is an equidigital number, since it uses as much as digits as its factorization.

2100203021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 300029010.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 2100203021 is about 45827.9720367376. The cubic root of 2100203021 is about 1280.6204310327.

Adding to 2100203021 its reverse (1203020012), we get a palindrome (3303223033).

The spelling of 2100203021 in words is "two billion, one hundred million, two hundred three thousand, twenty-one".