21765459152 has 20 divisors (see below), whose sum is σ = 42172882980. Its totient is φ = 10882134528.

The previous prime is 21765459151. The next prime is 21765459181. The reversal of 21765459152 is 25195456712.

It can be written as a sum of positive squares in 2 ways, for example, as 14936750656 + 6828708496 = 122216^2 + 82636^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21765459097 and 21765459106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21765459151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 497624 + ... + 539592.

It is an arithmetic number, because the mean of its divisors is an integer number (2108644149).

Almost surely, 2^21765459152 is an apocalyptic number.

It is an amenable number.

21765459152 is a deficient number, since it is larger than the sum of its proper divisors (20407423828).

21765459152 is a wasteful number, since it uses less digits than its factorization.

21765459152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74390 (or 74384 counting only the distinct ones).

The product of its digits is 756000, while the sum is 47.

The spelling of 21765459152 in words is "twenty-one billion, seven hundred sixty-five million, four hundred fifty-nine thousand, one hundred fifty-two".