66775745 has 8 divisors (see below), whose sum is σ = 84844584. Its totient is φ = 50278144.

The previous prime is 66775717. The next prime is 66775759. The reversal of 66775745 is 54757766.

It can be written as a sum of positive squares in 4 ways, for example, as 14010049 + 52765696 = 3743^2 + 7264^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66775745 - 2¹⁶ = 66710209 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66775745.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 392714 + ... + 392883.

It is an arithmetic number, because the mean of its divisors is an integer number (10605573).

Almost surely, 2^66775745 is an apocalyptic number.

It is an amenable number.

66775745 is a deficient number, since it is larger than the sum of its proper divisors (18068839).

66775745 is a wasteful number, since it uses less digits than its factorization.

66775745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 785619.

The product of its digits is 1234800, while the sum is 47.

The square root of 66775745 is about 8171.6427357050. The cubic root of 66775745 is about 405.7011580224.

The spelling of 66775745 in words is "sixty-six million, seven hundred seventy-five thousand, seven hundred forty-five".