21211221201099 has 4 divisors (see below), whose sum is σ = 28281628268136. Its totient is φ = 14140814134064.

The previous prime is 21211221201061. The next prime is 21211221201127. The reversal of 21211221201099 is 99010212211212.

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

It is a cyclic number.

It is not a de Polignac number, because 21211221201099 - 2²⁸ = 21210952765643 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21211221206099) 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, 3535203533514 + ... + 3535203533519.

It is an arithmetic number, because the mean of its divisors is an integer number (7070407067034).

Almost surely, 2^{21211221201099} is an apocalyptic number.

21211221201099 is a deficient number, since it is larger than the sum of its proper divisors (7070407067037).

21211221201099 is an equidigital number, since it uses as much as digits as its factorization.

21211221201099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7070407067036.

The product of its (nonzero) digits is 2592, while the sum is 33.

The spelling of 21211221201099 in words is "twenty-one trillion, two hundred eleven billion, two hundred twenty-one million, two hundred one thousand, ninety-nine".