66388875 has 48 divisors (see below), whose sum is σ = 128542752. Its totient is φ = 30340800.

The previous prime is 66388873. The next prime is 66388891. The reversal of 66388875 is 57888366.

It is not a de Polignac number, because 66388875 - 2¹ = 66388873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66388873) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 16569 + ... + 20181.

It is an arithmetic number, because the mean of its divisors is an integer number (2677974).

Almost surely, 2^66388875 is an apocalyptic number.

66388875 is a deficient number, since it is larger than the sum of its proper divisors (62153877).

66388875 is a wasteful number, since it uses less digits than its factorization.

66388875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3645 (or 3628 counting only the distinct ones).

The product of its digits is 1935360, while the sum is 51.

The square root of 66388875 is about 8147.9368554254. The cubic root of 66388875 is about 404.9161539581.

The spelling of 66388875 in words is "sixty-six million, three hundred eighty-eight thousand, eight hundred seventy-five".