213212621 has 2 divisors, whose sum is σ = 213212622. Its totient is φ = 213212620.

The previous prime is 213212609. The next prime is 213212627. The reversal of 213212621 is 126212312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 136562596 + 76650025 = 11686^2 + 8755^2 .

It is a cyclic number.

It is not a de Polignac number, because 213212621 - 2¹⁴ = 213196237 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 213212593 and 213212602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213212627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106606310 + 106606311.

It is an arithmetic number, because the mean of its divisors is an integer number (106606311).

Almost surely, 2^213212621 is an apocalyptic number.

It is an amenable number.

213212621 is a deficient number, since it is larger than the sum of its proper divisors (1).

213212621 is an equidigital number, since it uses as much as digits as its factorization.

213212621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 288, while the sum is 20.

The square root of 213212621 is about 14601.8019778382. The cubic root of 213212621 is about 597.4079114393.

Adding to 213212621 its reverse (126212312), we get a palindrome (339424933).

The spelling of 213212621 in words is "two hundred thirteen million, two hundred twelve thousand, six hundred twenty-one".