20020021220021 has 4 divisors (see below), whose sum is σ = 20097920135532. Its totient is φ = 19942122304512.

The previous prime is 20020021219963. The next prime is 20020021220027. The reversal of 20020021220021 is 12002212002002.

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 19671761901796 + 348259318225 = 4435286^2 + 590135^2 .

It is a cyclic number.

It is not a de Polignac number, because 20020021220021 - 2³⁰ = 20018947478197 is a prime.

It is a super-2 number, since 2×20020021220021² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20020021219978 and 20020021220005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20020021220027) 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, 38949457370 + ... + 38949457883.

It is an arithmetic number, because the mean of its divisors is an integer number (5024480033883).

Almost surely, 2^{20020021220021} is an apocalyptic number.

It is an amenable number.

20020021220021 is a deficient number, since it is larger than the sum of its proper divisors (77898915511).

20020021220021 is an equidigital number, since it uses as much as digits as its factorization.

20020021220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77898915510.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 20020021220021 its reverse (12002212002002), we get a palindrome (32022233222023).

The spelling of 20020021220021 in words is "twenty trillion, twenty billion, twenty-one million, two hundred twenty thousand, twenty-one".