212239021 has 2 divisors, whose sum is σ = 212239022. Its totient is φ = 212239020.

The previous prime is 212238997. The next prime is 212239031. The reversal of 212239021 is 120932212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 159516900 + 52722121 = 12630^2 + 7261^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212239021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 212238983 and 212239001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212239031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106119510 + 106119511.

It is an arithmetic number, because the mean of its divisors is an integer number (106119511).

Almost surely, 2^212239021 is an apocalyptic number.

It is an amenable number.

212239021 is a deficient number, since it is larger than the sum of its proper divisors (1).

212239021 is an equidigital number, since it uses as much as digits as its factorization.

212239021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 212239021 is about 14568.4254811562. The cubic root of 212239021 is about 596.4972025143.

The spelling of 212239021 in words is "two hundred twelve million, two hundred thirty-nine thousand, twenty-one".