212222421 has 12 divisors (see below), whose sum is σ = 306670572. Its totient is φ = 141422976.

The previous prime is 212222401. The next prime is 212222429. The reversal of 212222421 is 124222212.

212222421 is a `hidden beast` number, since 21 + 2 + 222 + 421 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 45037521 + 167184900 = 6711^2 + 12930^2 .

It is not a de Polignac number, because 212222421 - 2⁵ = 212222389 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 212222394 and 212222403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212222429) 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 in 11 ways as a sum of consecutive naturals, for example, 36315 + ... + 41751.

It is an arithmetic number, because the mean of its divisors is an integer number (25555881).

Almost surely, 2^212222421 is an apocalyptic number.

It is an amenable number.

212222421 is a deficient number, since it is larger than the sum of its proper divisors (94448151).

212222421 is a wasteful number, since it uses less digits than its factorization.

212222421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9780 (or 9777 counting only the distinct ones).

The product of its digits is 256, while the sum is 18.

The square root of 212222421 is about 14567.8557447553. The cubic root of 212222421 is about 596.4816506903.

Adding to 212222421 its reverse (124222212), we get a palindrome (336444633).

The spelling of 212222421 in words is "two hundred twelve million, two hundred twenty-two thousand, four hundred twenty-one".