66541445 has 4 divisors (see below), whose sum is σ = 79849740. Its totient is φ = 53233152.

The previous prime is 66541403. The next prime is 66541493. The reversal of 66541445 is 54414566.

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 14945956 + 51595489 = 3866^2 + 7183^2 .

It is a cyclic number.

It is not a de Polignac number, because 66541445 - 2⁶ = 66541381 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6654140 + ... + 6654149.

It is an arithmetic number, because the mean of its divisors is an integer number (19962435).

Almost surely, 2^66541445 is an apocalyptic number.

It is an amenable number.

66541445 is a deficient number, since it is larger than the sum of its proper divisors (13308295).

66541445 is a wasteful number, since it uses less digits than its factorization.

66541445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13308294.

The product of its digits is 57600, while the sum is 35.

The square root of 66541445 is about 8157.2939753328. The cubic root of 66541445 is about 405.2260994289.

The spelling of 66541445 in words is "sixty-six million, five hundred forty-one thousand, four hundred forty-five".