20121221201026 has 48 divisors (see below), whose sum is σ = 34320175626240. Its totient is φ = 8831607998400.

The previous prime is 20121221201009. The next prime is 20121221201027. The reversal of 20121221201026 is 62010212212102.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 20121221200988 and 20121221201006.

It is not an unprimeable number, because it can be changed into a prime (20121221201027) 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 23 ways as a sum of consecutive naturals, for example, 493935 + ... + 6362893.

It is an arithmetic number, because the mean of its divisors is an integer number (715003658880).

Almost surely, 2^{20121221201026} is an apocalyptic number.

20121221201026 is a deficient number, since it is larger than the sum of its proper divisors (14198954425214).

20121221201026 is a wasteful number, since it uses less digits than its factorization.

20121221201026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5869471 (or 5869460 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 22.

Adding to 20121221201026 its reverse (62010212212102), we get a palindrome (82131433413128).

The spelling of 20121221201026 in words is "twenty trillion, one hundred twenty-one billion, two hundred twenty-one million, two hundred one thousand, twenty-six".