212121201331 has 4 divisors (see below), whose sum is σ = 228438216832. Its totient is φ = 195804185832.

The previous prime is 212121201311. The next prime is 212121201343. The reversal of 212121201331 is 133102121212.

212121201331 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212121201331 is a prime.

It is a super-2 number, since 2×212121201331² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212121201299 and 212121201308.

It is not an unprimeable number, because it can be changed into a prime (212121201311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8158507731 + ... + 8158507756.

It is an arithmetic number, because the mean of its divisors is an integer number (57109554208).

Almost surely, 2^212121201331 is an apocalyptic number.

212121201331 is a deficient number, since it is larger than the sum of its proper divisors (16317015501).

212121201331 is a wasteful number, since it uses less digits than its factorization.

212121201331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16317015500.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 212121201331 its reverse (133102121212), we get a palindrome (345223322543).

The spelling of 212121201331 in words is "two hundred twelve billion, one hundred twenty-one million, two hundred one thousand, three hundred thirty-one".