21760869785 has 4 divisors (see below), whose sum is σ = 26113043748. Its totient is φ = 17408695824.

The previous prime is 21760869743. The next prime is 21760869799. The reversal of 21760869785 is 58796806712.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11179044361 + 10581825424 = 105731^2 + 102868^2 .

It is a cyclic number.

It is not a de Polignac number, because 21760869785 - 2¹² = 21760865689 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 2176086974 + ... + 2176086983.

It is an arithmetic number, because the mean of its divisors is an integer number (6528260937).

Almost surely, 2^21760869785 is an apocalyptic number.

It is an amenable number.

21760869785 is a deficient number, since it is larger than the sum of its proper divisors (4352173963).

21760869785 is an equidigital number, since it uses as much as digits as its factorization.

21760869785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4352173962.

The product of its (nonzero) digits is 10160640, while the sum is 59.

The spelling of 21760869785 in words is "twenty-one billion, seven hundred sixty million, eight hundred sixty-nine thousand, seven hundred eighty-five".