3121220120121 has 12 divisors (see below), whose sum is σ = 4508714665572. Its totient is φ = 2080681596576.

The previous prime is 3121220120111. The next prime is 3121220120141. The reversal of 3121220120121 is 1210210221213.

3121220120121 is a `hidden beast` number, since 31 + 212 + 201 + 201 + 21 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1971047523600 + 1150172596521 = 1403940^2 + 1072461^2 .

It is not a de Polignac number, because 3121220120121 - 2¹⁷ = 3121219989049 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 3121220120094 and 3121220120103.

It is not an unprimeable number, because it can be changed into a prime (3121220120111) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10834666 + ... + 11119011.

It is an arithmetic number, because the mean of its divisors is an integer number (375726222131).

Almost surely, 2^{3121220120121} is an apocalyptic number.

It is an amenable number.

3121220120121 is a deficient number, since it is larger than the sum of its proper divisors (1387494545451).

3121220120121 is a wasteful number, since it uses less digits than its factorization.

3121220120121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21969480 (or 21969477 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 3121220120121 its reverse (1210210221213), we get a palindrome (4331430341334).

The spelling of 3121220120121 in words is "three trillion, one hundred twenty-one billion, two hundred twenty million, one hundred twenty thousand, one hundred twenty-one".