212300021 has 2 divisors, whose sum is σ = 212300022. Its totient is φ = 212300020.

The previous prime is 212299991. The next prime is 212300057. The reversal of 212300021 is 120003212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 137217796 + 75082225 = 11714^2 + 8665^2 .

It is a cyclic number.

It is not a de Polignac number, because 212300021 - 2⁶ = 212299957 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 212299975 and 212300011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212300321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106150010 + 106150011.

It is an arithmetic number, because the mean of its divisors is an integer number (106150011).

Almost surely, 2^212300021 is an apocalyptic number.

It is an amenable number.

212300021 is a deficient number, since it is larger than the sum of its proper divisors (1).

212300021 is an equidigital number, since it uses as much as digits as its factorization.

212300021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 212300021 is about 14570.5188994764. The cubic root of 212300021 is about 596.5543438194.

Adding to 212300021 its reverse (120003212), we get a palindrome (332303233).

The spelling of 212300021 in words is "two hundred twelve million, three hundred thousand, twenty-one".