212312220221221 has 4 divisors (see below), whose sum is σ = 212332142557132. Its totient is φ = 212292297885312.

The previous prime is 212312220221141. The next prime is 212312220221279. The reversal of 212312220221221 is 122122022213212.

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 46926473084100 + 165385747137121 = 6850290^2 + 12860239^2 .

It is a cyclic number.

It is not a de Polignac number, because 212312220221221 - 2⁷ = 212312220221093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212312220221021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9961151970 + ... + 9961173283.

It is an arithmetic number, because the mean of its divisors is an integer number (53083035639283).

Almost surely, 2^{212312220221221} is an apocalyptic number.

It is an amenable number.

212312220221221 is a deficient number, since it is larger than the sum of its proper divisors (19922335911).

212312220221221 is a wasteful number, since it uses less digits than its factorization.

212312220221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19922335910.

The product of its (nonzero) digits is 1536, while the sum is 25.

Adding to 212312220221221 its reverse (122122022213212), we get a palindrome (334434242434433).

The spelling of 212312220221221 in words is "two hundred twelve trillion, three hundred twelve billion, two hundred twenty million, two hundred twenty-one thousand, two hundred twenty-one".