66775545 has 24 divisors (see below), whose sum is σ = 119737800. Its totient is φ = 34384896.

The previous prime is 66775537. The next prime is 66775549. The reversal of 66775545 is 54557766.

It can be written as a sum of positive squares in 4 ways, for example, as 385641 + 66389904 = 621^2 + 8148^2 .

It is not a de Polignac number, because 66775545 - 2³ = 66775537 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 66775545.

It is not an unprimeable number, because it can be changed into a prime (66775549) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 24280 + ... + 26889.

It is an arithmetic number, because the mean of its divisors is an integer number (4989075).

Almost surely, 2^66775545 is an apocalyptic number.

It is an amenable number.

66775545 is a deficient number, since it is larger than the sum of its proper divisors (52962255).

66775545 is a wasteful number, since it uses less digits than its factorization.

66775545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51209 (or 51206 counting only the distinct ones).

The product of its digits is 882000, while the sum is 45.

The square root of 66775545 is about 8171.6304982543. The cubic root of 66775545 is about 405.7007529835.

The spelling of 66775545 in words is "sixty-six million, seven hundred seventy-five thousand, five hundred forty-five".