1212100120021 has 48 divisors (see below), whose sum is σ = 1468832711808. Its totient is φ = 979675689600.

The previous prime is 1212100119977. The next prime is 1212100120051. The reversal of 1212100120021 is 1200210012121.

It is not a de Polignac number, because 1212100120021 - 2¹¹ = 1212100117973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1212100119983 and 1212100120010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212100120051) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 651315631 + ... + 651317491.

It is an arithmetic number, because the mean of its divisors is an integer number (30600681496).

Almost surely, 2^{1212100120021} is an apocalyptic number.

It is an amenable number.

1212100120021 is a deficient number, since it is larger than the sum of its proper divisors (256732591787).

1212100120021 is a wasteful number, since it uses less digits than its factorization.

1212100120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2970 (or 2951 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1212100120021 its reverse (1200210012121), we get a palindrome (2412310132142).

The spelling of 1212100120021 in words is "one trillion, two hundred twelve billion, one hundred million, one hundred twenty thousand, twenty-one".