21023400017 has 2 divisors, whose sum is σ = 21023400018. Its totient is φ = 21023400016.

The previous prime is 21023400011. The next prime is 21023400049. The reversal of 21023400017 is 71000432012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17211078481 + 3812321536 = 131191^2 + 61744^2 .

It is a cyclic number.

It is not a de Polignac number, because 21023400017 - 2²⁴ = 21006622801 is a prime.

It is not a weakly prime, because it can be changed into another prime (21023400011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511700008 + 10511700009.

It is an arithmetic number, because the mean of its divisors is an integer number (10511700009).

Almost surely, 2^21023400017 is an apocalyptic number.

It is an amenable number.

21023400017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21023400017 is an equidigital number, since it uses as much as digits as its factorization.

21023400017 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 20.

Adding to 21023400017 its reverse (71000432012), we get a palindrome (92023832029).

The spelling of 21023400017 in words is "twenty-one billion, twenty-three million, four hundred thousand, seventeen".