212021101 has 4 divisors (see below), whose sum is σ = 212539900.
Its totient is φ = 211502304.
The previous prime is 212021099. The next prime is 212021113. The reversal of 212021101 is 101120212.
Adding to 212021101 its reverse (101120212), we get a palindrome (313141313).
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 95942025 + 116079076 = 9795^2 + 10774^2
It is a cyclic number.
It is not a de Polignac number, because 212021101 - 21 = 212021099 is a prime.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (212021141) 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, 258786 + ... + 259603.
It is an arithmetic number, because the mean of its divisors is an integer number (53134975).
Almost surely, 2212021101 is an apocalyptic number.
It is an amenable number.
212021101 is a deficient number, since it is larger than the sum of its proper divisors (518799).
212021101 is an equidigital number, since it uses as much as digits as its factorization.
212021101 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 518798.
The product of its (nonzero) digits is 8, while the sum is 10.
The square root of 212021101 is about 14560.9443718462.
The cubic root of 212021101 is about 596.2929780751.
The spelling of 212021101 in words is "two hundred twelve million, twenty-one thousand, one hundred one".