212775725665 has 4 divisors (see below), whose sum is σ = 255330870804. Its totient is φ = 170220580528.

The previous prime is 212775725647. The next prime is 212775725671. The reversal of 212775725665 is 566527577212.

212775725665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 160653465856 + 52122259809 = 400816^2 + 228303^2 .

It is a cyclic number.

It is not a de Polignac number, because 212775725665 - 2⁷ = 212775725537 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 (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21277572562 + ... + 21277572571.

It is an arithmetic number, because the mean of its divisors is an integer number (63832717701).

Almost surely, 2^212775725665 is an apocalyptic number.

It is an amenable number.

212775725665 is a deficient number, since it is larger than the sum of its proper divisors (42555145139).

212775725665 is an equidigital number, since it uses as much as digits as its factorization.

212775725665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42555145138.

The product of its digits is 12348000, while the sum is 55.

The spelling of 212775725665 in words is "two hundred twelve billion, seven hundred seventy-five million, seven hundred twenty-five thousand, six hundred sixty-five".