2121208686 has 12 divisors (see below), whose sum is σ = 4595952192. Its totient is φ = 707069556.

The previous prime is 2121208681. The next prime is 2121208703. The reversal of 2121208686 is 6868021212.

It is a super-3 number, since 3×2121208686³ (a number of 29 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2121208686.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121208681) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 58922446 + ... + 58922481.

It is an arithmetic number, because the mean of its divisors is an integer number (382996016).

Almost surely, 2^2121208686 is an apocalyptic number.

2121208686 is an abundant number, since it is smaller than the sum of its proper divisors (2474743506).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2121208686 is a wasteful number, since it uses less digits than its factorization.

2121208686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117844935 (or 117844932 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 2121208686 is about 46056.5813538087. The cubic root of 2121208686 is about 1284.8757491130.

Adding to 2121208686 its reverse (6868021212), we get a palindrome (8989229898).

The spelling of 2121208686 in words is "two billion, one hundred twenty-one million, two hundred eight thousand, six hundred eighty-six".