66375387 has 24 divisors (see below), whose sum is σ = 103525968. Its totient is φ = 40737600.

The previous prime is 66375367. The next prime is 66375389. The reversal of 66375387 is 78357366.

66375387 is a `hidden beast` number, since 6 + 637 + 5 + 3 + 8 + 7 = 666.

It is not a de Polignac number, because 66375387 - 2¹¹ = 66373339 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66375389) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80437 + ... + 81257.

It is an arithmetic number, because the mean of its divisors is an integer number (4313582).

Almost surely, 2^66375387 is an apocalyptic number.

66375387 is a deficient number, since it is larger than the sum of its proper divisors (37150581).

66375387 is a wasteful number, since it uses less digits than its factorization.

66375387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1531 (or 1528 counting only the distinct ones).

The product of its digits is 635040, while the sum is 45.

The square root of 66375387 is about 8147.1091191907. The cubic root of 66375387 is about 404.8887302922. Note that the first 3 decimals are identical.

The spelling of 66375387 in words is "sixty-six million, three hundred seventy-five thousand, three hundred eighty-seven".