66511545 has 16 divisors (see below), whose sum is σ = 106652160. Its totient is φ = 35394944.

The previous prime is 66511537. The next prime is 66511547. The reversal of 66511545 is 54511566.

It is a cyclic number.

It is not a de Polignac number, because 66511545 - 2³ = 66511537 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66511547) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 2557 + ... + 11813.

It is an arithmetic number, because the mean of its divisors is an integer number (6665760).

Almost surely, 2^66511545 is an apocalyptic number.

It is an amenable number.

66511545 is a deficient number, since it is larger than the sum of its proper divisors (40140615).

66511545 is a wasteful number, since it uses less digits than its factorization.

66511545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9744.

The product of its digits is 18000, while the sum is 33.

The square root of 66511545 is about 8155.4610537970. The cubic root of 66511545 is about 405.1653950282.

The spelling of 66511545 in words is "sixty-six million, five hundred eleven thousand, five hundred forty-five".