66531447 has 12 divisors (see below), whose sum is σ = 96804240. Its totient is φ = 44029728.

The previous prime is 66531403. The next prime is 66531457. The reversal of 66531447 is 74413566.

It is a happy number.

It is not a de Polignac number, because 66531447 - 2⁶ = 66531383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66531457) 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 11 ways as a sum of consecutive naturals, for example, 25747 + ... + 28212.

It is an arithmetic number, because the mean of its divisors is an integer number (8067020).

Almost surely, 2^66531447 is an apocalyptic number.

66531447 is a deficient number, since it is larger than the sum of its proper divisors (30272793).

66531447 is a wasteful number, since it uses less digits than its factorization.

66531447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54102 (or 54099 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The square root of 66531447 is about 8156.6811265367. The cubic root of 66531447 is about 405.2058030383.

It can be divided in two parts, 6653 and 1447, that added together give a square (8100 = 90²).

The spelling of 66531447 in words is "sixty-six million, five hundred thirty-one thousand, four hundred forty-seven".