212000009988821 has 2 divisors, whose sum is σ = 212000009988822. Its totient is φ = 212000009988820.

The previous prime is 212000009988797. The next prime is 212000009988911. The reversal of 212000009988821 is 128889900000212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 211348501108900 + 651508879921 = 14537830^2 + 807161^2 .

It is a cyclic number.

It is not a de Polignac number, because 212000009988821 - 2⁶ = 212000009988757 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 212000009988821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212000009088821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106000004994410 + 106000004994411.

It is an arithmetic number, because the mean of its divisors is an integer number (106000004994411).

Almost surely, 2^{212000009988821} is an apocalyptic number.

It is an amenable number.

212000009988821 is a deficient number, since it is larger than the sum of its proper divisors (1).

212000009988821 is an equidigital number, since it uses as much as digits as its factorization.

212000009988821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 331776, while the sum is 50.

The spelling of 212000009988821 in words is "two hundred twelve trillion, nine million, nine hundred eighty-eight thousand, eight hundred twenty-one".