21964446169 has 2 divisors, whose sum is σ = 21964446170. Its totient is φ = 21964446168.

The previous prime is 21964446067. The next prime is 21964446181. The reversal of 21964446169 is 96164446912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19913443225 + 2051002944 = 141115^2 + 45288^2 .

It is a cyclic number.

It is not a de Polignac number, because 21964446169 - 2¹¹ = 21964444121 is a prime.

It is a super-2 number, since 2×21964446169² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21964444169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10982223084 + 10982223085.

It is an arithmetic number, because the mean of its divisors is an integer number (10982223085).

Almost surely, 2^21964446169 is an apocalyptic number.

It is an amenable number.

21964446169 is a deficient number, since it is larger than the sum of its proper divisors (1).

21964446169 is an equidigital number, since it uses as much as digits as its factorization.

21964446169 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2239488, while the sum is 52.

The spelling of 21964446169 in words is "twenty-one billion, nine hundred sixty-four million, four hundred forty-six thousand, one hundred sixty-nine".