21795502689 has 9 divisors (see below), whose sum is σ = 31483032529. Its totient is φ = 14530039860.

The previous prime is 21795502679. The next prime is 21795502691. The reversal of 21795502689 is 98620559712.

The square root of 21795502689 is 147633.

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

21795502689 is a `hidden beast` number, since 2 + 1 + 7 + 9 + 550 + 2 + 6 + 89 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 21795502689 - 2⁵ = 21795502657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21795502649) 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 8 ways as a sum of consecutive naturals, for example, 418294 + ... + 467504.

Almost surely, 2^21795502689 is an apocalyptic number.

21795502689 is the 147633-rd square number.

21795502689 is the 73817-th centered octagonal number.

It is an amenable number.

21795502689 is a deficient number, since it is larger than the sum of its proper divisors (9687529840).

21795502689 is an frugal number, since it uses more digits than its factorization.

21795502689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98428 (or 49214 counting only the distinct ones).

The product of its (nonzero) digits is 2721600, while the sum is 54.

The spelling of 21795502689 in words is "twenty-one billion, seven hundred ninety-five million, five hundred two thousand, six hundred eighty-nine".