212330621 has 4 divisors (see below), whose sum is σ = 212498172. Its totient is φ = 212163072.

The previous prime is 212330617. The next prime is 212330633. The reversal of 212330621 is 126033212.

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 116877721 + 95452900 = 10811^2 + 9770^2 .

It is a cyclic number.

It is not a de Polignac number, because 212330621 - 2² = 212330617 is a prime.

It is a super-2 number, since 2×212330621² = 90168585228491282, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 212330593 and 212330602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212330821) 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 in 3 ways as a sum of consecutive naturals, for example, 81860 + ... + 84413.

It is an arithmetic number, because the mean of its divisors is an integer number (53124543).

Almost surely, 2^212330621 is an apocalyptic number.

It is an amenable number.

212330621 is a deficient number, since it is larger than the sum of its proper divisors (167551).

212330621 is a wasteful number, since it uses less digits than its factorization.

212330621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167550.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 212330621 is about 14571.5689271952. The cubic root of 212330621 is about 596.5830040238.

Adding to 212330621 its reverse (126033212), we get a palindrome (338363833).

The spelling of 212330621 in words is "two hundred twelve million, three hundred thirty thousand, six hundred twenty-one".