1211050213821 has 16 divisors (see below), whose sum is σ = 2050455388800. Its totient is φ = 692028693504.

The previous prime is 1211050213811. The next prime is 1211050213853. The reversal of 1211050213821 is 1283120501121.

1211050213821 is a `hidden beast` number, since 1 + 2 + 1 + 1 + 0 + 502 + 138 + 21 = 666.

It is not a de Polignac number, because 1211050213821 - 2¹¹ = 1211050211773 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211050213801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3203836356 + ... + 3203836733.

It is an arithmetic number, because the mean of its divisors is an integer number (128153461800).

Almost surely, 2^{1211050213821} is an apocalyptic number.

It is an amenable number.

1211050213821 is a deficient number, since it is larger than the sum of its proper divisors (839405174979).

1211050213821 is an equidigital number, since it uses as much as digits as its factorization.

1211050213821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6407673105 (or 6407673099 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 27.

Adding to 1211050213821 its reverse (1283120501121), we get a palindrome (2494170714942).

The spelling of 1211050213821 in words is "one trillion, two hundred eleven billion, fifty million, two hundred thirteen thousand, eight hundred twenty-one".