20120121212121 has 32 divisors (see below), whose sum is σ = 34067174481920. Its totient is φ = 11496752854992.

The previous prime is 20120121212111. The next prime is 20120121212131. The reversal of 20120121212121 is 12121212102102.

It is an interprime number because it is at equal distance from previous prime (20120121212111) and next prime (20120121212131).

It is not a de Polignac number, because 20120121212121 - 2⁵ = 20120121212089 is a prime.

It is a Duffinian number.

20120121212121 is a modest number, since divided by 21212121 gives 201201 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 20120121212094 and 20120121212103.

It is not an unprimeable number, because it can be changed into a prime (20120121212111) 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 31 ways as a sum of consecutive naturals, for example, 2645946 + ... + 6873228.

It is an arithmetic number, because the mean of its divisors is an integer number (1064599202560).

Almost surely, 2^{20120121212121} is an apocalyptic number.

20120121212121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20120121212121 is a deficient number, since it is larger than the sum of its proper divisors (13947053269799).

20120121212121 is a wasteful number, since it uses less digits than its factorization.

20120121212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4252482 (or 4252476 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 20120121212121 its reverse (12121212102102), we get a palindrome (32241333314223).

The spelling of 20120121212121 in words is "twenty trillion, one hundred twenty billion, one hundred twenty-one million, two hundred twelve thousand, one hundred twenty-one".