21786956959 has 2 divisors, whose sum is σ = 21786956960. Its totient is φ = 21786956958.

The previous prime is 21786956957. The next prime is 21786956987. The reversal of 21786956959 is 95965968712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21786956959 - 2¹ = 21786956957 is a prime.

Together with 21786956957, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21786956894 and 21786956903.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21786956957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10893478479 + 10893478480.

It is an arithmetic number, because the mean of its divisors is an integer number (10893478480).

Almost surely, 2^21786956959 is an apocalyptic number.

21786956959 is a deficient number, since it is larger than the sum of its proper divisors (1).

21786956959 is an equidigital number, since it uses as much as digits as its factorization.

21786956959 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 73483200, while the sum is 67.

The spelling of 21786956959 in words is "twenty-one billion, seven hundred eighty-six million, nine hundred fifty-six thousand, nine hundred fifty-nine".