20420111213 has 4 divisors (see below), whose sum is σ = 20918162748. Its totient is φ = 19922059680.

The previous prime is 20420111143. The next prime is 20420111233. The reversal of 20420111213 is 31211102402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31211102402 = 2 ⋅15605551201.

It can be written as a sum of positive squares in 2 ways, for example, as 8089563364 + 12330547849 = 89942^2 + 111043^2 .

It is a cyclic number.

It is not a de Polignac number, because 20420111213 - 2¹⁰ = 20420110189 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20420111191 and 20420111200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20420111233) 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, 249025706 + ... + 249025787.

It is an arithmetic number, because the mean of its divisors is an integer number (5229540687).

Almost surely, 2^20420111213 is an apocalyptic number.

It is an amenable number.

20420111213 is a deficient number, since it is larger than the sum of its proper divisors (498051535).

20420111213 is an equidigital number, since it uses as much as digits as its factorization.

20420111213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498051534.

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

Adding to 20420111213 its reverse (31211102402), we get a palindrome (51631213615).

The spelling of 20420111213 in words is "twenty billion, four hundred twenty million, one hundred eleven thousand, two hundred thirteen".