2100021222121 has 16 divisors (see below), whose sum is σ = 2200771584000. Its totient is φ = 2000065692240.

The previous prime is 2100021222113. The next prime is 2100021222133. The reversal of 2100021222121 is 1212221200012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2100021222121 - 2³ = 2100021222113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2100021222095 and 2100021222104.

It is not an unprimeable number, because it can be changed into a prime (2100021222181) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12005116 + ... + 12178786.

It is an arithmetic number, because the mean of its divisors is an integer number (137548224000).

Almost surely, 2^{2100021222121} is an apocalyptic number.

It is an amenable number.

2100021222121 is a deficient number, since it is larger than the sum of its proper divisors (100750361879).

2100021222121 is a wasteful number, since it uses less digits than its factorization.

2100021222121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175956.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 2100021222121 its reverse (1212221200012), we get a palindrome (3312242422133).

The spelling of 2100021222121 in words is "two trillion, one hundred billion, twenty-one million, two hundred twenty-two thousand, one hundred twenty-one".