21108802163 has 2 divisors, whose sum is σ = 21108802164. Its totient is φ = 21108802162.

The previous prime is 21108802147. The next prime is 21108802219. The reversal of 21108802163 is 36120880112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21108802163 - 2⁴ = 21108802147 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21108802763) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10554401081 + 10554401082.

It is an arithmetic number, because the mean of its divisors is an integer number (10554401082).

Almost surely, 2^21108802163 is an apocalyptic number.

21108802163 is a deficient number, since it is larger than the sum of its proper divisors (1).

21108802163 is an equidigital number, since it uses as much as digits as its factorization.

21108802163 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 32.

The spelling of 21108802163 in words is "twenty-one billion, one hundred eight million, eight hundred two thousand, one hundred sixty-three".