220121201021 has 4 divisors (see below), whose sum is σ = 225490010844. Its totient is φ = 214752391200.

The previous prime is 220121201009. The next prime is 220121201039. The reversal of 220121201021 is 120102121022.

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 77290116121 + 142831084900 = 278011^2 + 377930^2 .

It is not a de Polignac number, because 220121201021 - 2¹⁴ = 220121184637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 220121200987 and 220121201005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220121201071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2684404850 + ... + 2684404931.

It is an arithmetic number, because the mean of its divisors is an integer number (56372502711).

Almost surely, 2^220121201021 is an apocalyptic number.

It is an amenable number.

220121201021 is a deficient number, since it is larger than the sum of its proper divisors (5368809823).

220121201021 is an equidigital number, since it uses as much as digits as its factorization.

220121201021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5368809822.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 220121201021 its reverse (120102121022), we get a palindrome (340223322043).

The spelling of 220121201021 in words is "two hundred twenty billion, one hundred twenty-one million, two hundred one thousand, twenty-one".