21885018893 has 2 divisors, whose sum is σ = 21885018894. Its totient is φ = 21885018892.

The previous prime is 21885018803. The next prime is 21885018931. The reversal of 21885018893 is 39881058812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21668428804 + 216590089 = 147202^2 + 14717^2 .

It is a cyclic number.

It is not a de Polignac number, because 21885018893 - 2¹² = 21885014797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21885018803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10942509446 + 10942509447.

It is an arithmetic number, because the mean of its divisors is an integer number (10942509447).

Almost surely, 2^21885018893 is an apocalyptic number.

It is an amenable number.

21885018893 is a deficient number, since it is larger than the sum of its proper divisors (1).

21885018893 is an equidigital number, since it uses as much as digits as its factorization.

21885018893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1105920, while the sum is 53.

The spelling of 21885018893 in words is "twenty-one billion, eight hundred eighty-five million, eighteen thousand, eight hundred ninety-three".