1220021121321 has 12 divisors (see below), whose sum is σ = 1865914656372. Its totient is φ = 765503448576.

The previous prime is 1220021121313. The next prime is 1220021121383. The reversal of 1220021121321 is 1231211200221.

1220021121321 is a `hidden beast` number, since 1 + 2 + 200 + 21 + 121 + 321 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1136219556096 + 83801565225 = 1065936^2 + 289485^2 .

It is not a de Polignac number, because 1220021121321 - 2³ = 1220021121313 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1220021121294 and 1220021121303.

It is not an unprimeable number, because it can be changed into a prime (1220021120321) 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, 3986996976 + ... + 3986997281.

It is an arithmetic number, because the mean of its divisors is an integer number (155492888031).

Almost surely, 2^{1220021121321} is an apocalyptic number.

It is an amenable number.

1220021121321 is a deficient number, since it is larger than the sum of its proper divisors (645893535051).

1220021121321 is a wasteful number, since it uses less digits than its factorization.

1220021121321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7973994280 (or 7973994277 counting only the distinct ones).

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

Adding to 1220021121321 its reverse (1231211200221), we get a palindrome (2451232321542).

The spelling of 1220021121321 in words is "one trillion, two hundred twenty billion, twenty-one million, one hundred twenty-one thousand, three hundred twenty-one".