2101211100021 has 16 divisors (see below), whose sum is σ = 3071821313088. Its totient is φ = 1266996998400.

The previous prime is 2101211099983. The next prime is 2101211100083. The reversal of 2101211100021 is 1200011121012.

It is not a de Polignac number, because 2101211100021 - 2¹⁷ = 2101210968949 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2101211100421) 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, 161600260 + ... + 161613261.

It is an arithmetic number, because the mean of its divisors is an integer number (191988832068).

Almost surely, 2^{2101211100021} is an apocalyptic number.

It is an amenable number.

2101211100021 is a deficient number, since it is larger than the sum of its proper divisors (970610213067).

2101211100021 is a wasteful number, since it uses less digits than its factorization.

2101211100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323213732.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 2101211100021 its reverse (1200011121012), we get a palindrome (3301222221033).

The spelling of 2101211100021 in words is "two trillion, one hundred one billion, two hundred eleven million, one hundred thousand, twenty-one".