21010100221211 has 4 divisors (see below), whose sum is σ = 21046895493624. Its totient is φ = 20973304948800.

The previous prime is 21010100221207. The next prime is 21010100221213. The reversal of 21010100221211 is 11212200101012.

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 21010100221211 - 2² = 21010100221207 is a prime.

It is a super-2 number, since 2×21010100221211² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21010100221213) 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, 18397635350 + ... + 18397636491.

It is an arithmetic number, because the mean of its divisors is an integer number (5261723873406).

Almost surely, 2^{21010100221211} is an apocalyptic number.

21010100221211 is a deficient number, since it is larger than the sum of its proper divisors (36795272413).

21010100221211 is an equidigital number, since it uses as much as digits as its factorization.

21010100221211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36795272412.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21010100221211 its reverse (11212200101012), we get a palindrome (32222300322223).

The spelling of 21010100221211 in words is "twenty-one trillion, ten billion, one hundred million, two hundred twenty-one thousand, two hundred eleven".