21201020023 has 2 divisors, whose sum is σ = 21201020024. Its totient is φ = 21201020022.

The previous prime is 21201020003. The next prime is 21201020041. The reversal of 21201020023 is 32002010212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21201020023 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21201019985 and 21201020012.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21201020003) 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, 10600510011 + 10600510012.

It is an arithmetic number, because the mean of its divisors is an integer number (10600510012).

Almost surely, 2^21201020023 is an apocalyptic number.

21201020023 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201020023 is an equidigital number, since it uses as much as digits as its factorization.

21201020023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 21201020023 its reverse (32002010212), we get a palindrome (53203030235).

The spelling of 21201020023 in words is "twenty-one billion, two hundred one million, twenty thousand, twenty-three".