21803641896969 has 243 divisors, whose sum is σ = 35566223746599. Its totient is φ = 12869715481920.

The previous prime is 21803641896899. The next prime is 21803641896977. The reversal of 21803641896969 is 96969814630812.

The square root of 21803641896969 is 4669437.

It is a perfect power (a square), and thus also a powerful number.

21803641896969 is a `hidden beast` number, since 2 + 1 + 8 + 0 + 36 + 418 + 96 + 96 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19510198191225 + 2293443705744 = 4417035^2 + 1514412^2 .

It is not a de Polignac number, because 21803641896969 - 2⁹ = 21803641896457 is a prime.

It is a super-2 number, since 2×21803641896969² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (72) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21803641896897 and 21803641896906.

It is not an unprimeable number, because it can be changed into a prime (21803641896769) 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 in 242 ways as a sum of consecutive naturals, for example, 369553252462 + ... + 369553252520.

Almost surely, 2^{21803641896969} is an apocalyptic number.

21803641896969 is the 4669437-th square number.

21803641896969 is the 2334719-th centered octagonal number.

It is an amenable number.

21803641896969 is a deficient number, since it is larger than the sum of its proper divisors (13762581849630).

21803641896969 is an equidigital number, since it uses as much as digits as its factorization.

21803641896969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306 (or 153 counting only the distinct ones).

The product of its (nonzero) digits is 241864704, while the sum is 72.

The spelling of 21803641896969 in words is "twenty-one trillion, eight hundred three billion, six hundred forty-one million, eight hundred ninety-six thousand, nine hundred sixty-nine".