21881118811 has 2 divisors, whose sum is σ = 21881118812. Its totient is φ = 21881118810.

The previous prime is 21881118799. The next prime is 21881118823. The reversal of 21881118811 is 11881118812.

It is a balanced prime because it is at equal distance from previous prime (21881118799) and next prime (21881118823).

It is a cyclic number.

It is not a de Polignac number, because 21881118811 - 2²⁷ = 21746901083 is a prime.

It is not a weakly prime, because it can be changed into another prime (21881118881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10940559405 + 10940559406.

It is an arithmetic number, because the mean of its divisors is an integer number (10940559406).

Almost surely, 2^21881118811 is an apocalyptic number.

21881118811 is a deficient number, since it is larger than the sum of its proper divisors (1).

21881118811 is an equidigital number, since it uses as much as digits as its factorization.

21881118811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8192, while the sum is 40.

Subtracting from 21881118811 its reverse (11881118812), we obtain a palindrome (9999999999).

The spelling of 21881118811 in words is "twenty-one billion, eight hundred eighty-one million, one hundred eighteen thousand, eight hundred eleven".