212106621 has 8 divisors (see below), whose sum is σ = 295104960. Its totient is φ = 135256352.

The previous prime is 212106613. The next prime is 212106649. The reversal of 212106621 is 126601212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 212106621 - 2³ = 212106613 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212106611) 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 7 ways as a sum of consecutive naturals, for example, 1536936 + ... + 1537073.

It is an arithmetic number, because the mean of its divisors is an integer number (36888120).

Almost surely, 2^212106621 is an apocalyptic number.

It is an amenable number.

212106621 is a deficient number, since it is larger than the sum of its proper divisors (82998339).

212106621 is a wasteful number, since it uses less digits than its factorization.

212106621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3074035.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 212106621 is about 14563.8806984952. The cubic root of 212106621 is about 596.3731400974.

Adding to 212106621 its reverse (126601212), we get a palindrome (338707833).

The spelling of 212106621 in words is "two hundred twelve million, one hundred six thousand, six hundred twenty-one".