21802855423 has 2 divisors, whose sum is σ = 21802855424. Its totient is φ = 21802855422.

The previous prime is 21802855409. The next prime is 21802855447. The reversal of 21802855423 is 32455820812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21802855423 - 2⁵ = 21802855391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21802855223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10901427711 + 10901427712.

It is an arithmetic number, because the mean of its divisors is an integer number (10901427712).

Almost surely, 2^21802855423 is an apocalyptic number.

21802855423 is a deficient number, since it is larger than the sum of its proper divisors (1).

21802855423 is an equidigital number, since it uses as much as digits as its factorization.

21802855423 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 153600, while the sum is 40.

The spelling of 21802855423 in words is "twenty-one billion, eight hundred two million, eight hundred fifty-five thousand, four hundred twenty-three".