212012021 has 12 divisors (see below), whose sum is σ = 231276132. Its totient is φ = 194253696.

The previous prime is 212011993. The next prime is 212012033. The reversal of 212012021 is 120210212.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 58599025 + 153412996 = 7655^2 + 12386^2 .

It is a de Polignac number, because none of the positive numbers 2^k-212012021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212011993 and 212012011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212012071) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18575 + ... + 27731.

It is an arithmetic number, because the mean of its divisors is an integer number (19273011).

Almost surely, 2^212012021 is an apocalyptic number.

It is an amenable number.

212012021 is a deficient number, since it is larger than the sum of its proper divisors (19264111).

212012021 is a wasteful number, since it uses less digits than its factorization.

212012021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9320 (or 9307 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 212012021 is about 14560.6325755442. The cubic root of 212012021 is about 596.2844656873.

Adding to 212012021 its reverse (120210212), we get a palindrome (332222233).

It can be divided in two parts, 2120 and 12021, that added together give a palindrome (14141).

The spelling of 212012021 in words is "two hundred twelve million, twelve thousand, twenty-one".