21100020023 has 2 divisors, whose sum is σ = 21100020024. Its totient is φ = 21100020022.

The previous prime is 21100020001. The next prime is 21100020037. The reversal of 21100020023 is 32002000112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21100020023 - 2²⁰ = 21098971447 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21100019986 and 21100020013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21100022023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550010011 + 10550010012.

It is an arithmetic number, because the mean of its divisors is an integer number (10550010012).

Almost surely, 2^21100020023 is an apocalyptic number.

21100020023 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100020023 is an equidigital number, since it uses as much as digits as its factorization.

21100020023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 11.

Adding to 21100020023 its reverse (32002000112), we get a palindrome (53102020135).

The spelling of 21100020023 in words is "twenty-one billion, one hundred million, twenty thousand, twenty-three".