21203544223 has 2 divisors, whose sum is σ = 21203544224. Its totient is φ = 21203544222.

The previous prime is 21203544217. The next prime is 21203544227. The reversal of 21203544223 is 32244530212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21203544223 - 2¹³ = 21203536031 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21203544191 and 21203544200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21203544227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601772111 + 10601772112.

It is an arithmetic number, because the mean of its divisors is an integer number (10601772112).

Almost surely, 2^21203544223 is an apocalyptic number.

21203544223 is a deficient number, since it is larger than the sum of its proper divisors (1).

21203544223 is an equidigital number, since it uses as much as digits as its factorization.

21203544223 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11520, while the sum is 28.

The spelling of 21203544223 in words is "twenty-one billion, two hundred three million, five hundred forty-four thousand, two hundred twenty-three".