212010220021 has 4 divisors (see below), whose sum is σ = 224481409452. Its totient is φ = 199539030592.

The previous prime is 212010220013. The next prime is 212010220031. The reversal of 212010220021 is 120022010212.

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 68531386225 + 143478833796 = 261785^2 + 378786^2 .

It is a cyclic number.

It is not a de Polignac number, because 212010220021 - 2³ = 212010220013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212010219983 and 212010220010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212010220031) 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, 6235594690 + ... + 6235594723.

It is an arithmetic number, because the mean of its divisors is an integer number (56120352363).

Almost surely, 2^212010220021 is an apocalyptic number.

It is an amenable number.

212010220021 is a deficient number, since it is larger than the sum of its proper divisors (12471189431).

212010220021 is a wasteful number, since it uses less digits than its factorization.

212010220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12471189430.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 212010220021 its reverse (120022010212), we get a palindrome (332032230233).

The spelling of 212010220021 in words is "two hundred twelve billion, ten million, two hundred twenty thousand, twenty-one".