2100002012021 has 4 divisors (see below), whose sum is σ = 2100104426700. Its totient is φ = 2099899597344.

The previous prime is 2100002011967. The next prime is 2100002012083. The reversal of 2100002012021 is 1202102000012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 569400031396 + 1530601980625 = 754586^2 + 1237175^2 .

It is a cyclic number.

It is not a de Polignac number, because 2100002012021 - 2⁶ = 2100002011957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2100002011993 and 2100002012011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100002012621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51176576 + ... + 51217593.

It is an arithmetic number, because the mean of its divisors is an integer number (525026106675).

Almost surely, 2^{2100002012021} is an apocalyptic number.

It is an amenable number.

2100002012021 is a deficient number, since it is larger than the sum of its proper divisors (102414679).

2100002012021 is a wasteful number, since it uses less digits than its factorization.

2100002012021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102414678.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 2100002012021 its reverse (1202102000012), we get a palindrome (3302104012033).

The spelling of 2100002012021 in words is "two trillion, one hundred billion, two million, twelve thousand, twenty-one".