211221212210101 has 4 divisors (see below), whose sum is σ = 211249266569100. Its totient is φ = 211193157851104.

The previous prime is 211221212210083. The next prime is 211221212210117. The reversal of 211221212210101 is 101012212122112.

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 158649794331876 + 52571417878225 = 12595626^2 + 7250615^2 .

It is a cyclic number.

It is not a de Polignac number, because 211221212210101 - 2⁹ = 211221212209589 is a prime.

It is a super-2 number, since 2×211221212210101² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221212210131) 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, 14027168206 + ... + 14027183263.

It is an arithmetic number, because the mean of its divisors is an integer number (52812316642275).

Almost surely, 2^{211221212210101} is an apocalyptic number.

It is an amenable number.

211221212210101 is a deficient number, since it is larger than the sum of its proper divisors (28054358999).

211221212210101 is an equidigital number, since it uses as much as digits as its factorization.

211221212210101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28054358998.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 211221212210101 its reverse (101012212122112), we get a palindrome (312233424332213).

The spelling of 211221212210101 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twelve million, two hundred ten thousand, one hundred one".