20212121023 has 2 divisors, whose sum is σ = 20212121024. Its totient is φ = 20212121022.

The previous prime is 20212121021. The next prime is 20212121029. The reversal of 20212121023 is 32012121202.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20212121023 - 2¹ = 20212121021 is a prime.

Together with 20212121021, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 20212120988 and 20212121006.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20212121021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10106060511 + 10106060512.

It is an arithmetic number, because the mean of its divisors is an integer number (10106060512).

Almost surely, 2^20212121023 is an apocalyptic number.

20212121023 is a deficient number, since it is larger than the sum of its proper divisors (1).

20212121023 is an equidigital number, since it uses as much as digits as its factorization.

20212121023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 20212121023 its reverse (32012121202), we get a palindrome (52224242225).

The spelling of 20212121023 in words is "twenty billion, two hundred twelve million, one hundred twenty-one thousand, twenty-three".