66545247 has 16 divisors (see below), whose sum is σ = 90616320. Its totient is φ = 43428000.

The previous prime is 66545243. The next prime is 66545257. The reversal of 66545247 is 74254566.

It is not a de Polignac number, because 66545247 - 2² = 66545243 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66545243) 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 15 ways as a sum of consecutive naturals, for example, 31129 + ... + 33197.

It is an arithmetic number, because the mean of its divisors is an integer number (5663520).

Almost surely, 2^66545247 is an apocalyptic number.

66545247 is a deficient number, since it is larger than the sum of its proper divisors (24071073).

66545247 is a wasteful number, since it uses less digits than its factorization.

66545247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2294.

The product of its digits is 201600, while the sum is 39.

The square root of 66545247 is about 8157.5270149721. The cubic root of 66545247 is about 405.2338171267.

The spelling of 66545247 in words is "sixty-six million, five hundred forty-five thousand, two hundred forty-seven".