1220120032121 has 4 divisors (see below), whose sum is σ = 1221232266612. Its totient is φ = 1219007797632.

The previous prime is 1220120032111. The next prime is 1220120032123. The reversal of 1220120032121 is 1212300210221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 462461202025 + 757658830096 = 680045^2 + 870436^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220120032121 - 2¹⁸ = 1220119769977 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1220120032121.

It is not an unprimeable number, because it can be changed into a prime (1220120032123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 556115600 + ... + 556117793.

It is an arithmetic number, because the mean of its divisors is an integer number (305308066653).

Almost surely, 2^{1220120032121} is an apocalyptic number.

It is an amenable number.

1220120032121 is a deficient number, since it is larger than the sum of its proper divisors (1112234491).

1220120032121 is a wasteful number, since it uses less digits than its factorization.

1220120032121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1112234490.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 1220120032121 its reverse (1212300210221), we get a palindrome (2432420242342).

The spelling of 1220120032121 in words is "one trillion, two hundred twenty billion, one hundred twenty million, thirty-two thousand, one hundred twenty-one".