21655312183 has 2 divisors, whose sum is σ = 21655312184. Its totient is φ = 21655312182.

The previous prime is 21655312141. The next prime is 21655312223. The reversal of 21655312183 is 38121355612.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21655312183 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21655112183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10827656091 + 10827656092.

It is an arithmetic number, because the mean of its divisors is an integer number (10827656092).

Almost surely, 2^21655312183 is an apocalyptic number.

21655312183 is a deficient number, since it is larger than the sum of its proper divisors (1).

21655312183 is an equidigital number, since it uses as much as digits as its factorization.

21655312183 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43200, while the sum is 37.

Adding to 21655312183 its reverse (38121355612), we get a palindrome (59776667795).

The spelling of 21655312183 in words is "twenty-one billion, six hundred fifty-five million, three hundred twelve thousand, one hundred eighty-three".