66440787 has 16 divisors (see below), whose sum is σ = 103713792. Its totient is φ = 37039680.

The previous prime is 66440779. The next prime is 66440797. The reversal of 66440787 is 78704466.

It is not a de Polignac number, because 66440787 - 2³ = 66440779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66440707) 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, 37723 + ... + 39444.

It is an arithmetic number, because the mean of its divisors is an integer number (6482112).

Almost surely, 2^66440787 is an apocalyptic number.

66440787 is a deficient number, since it is larger than the sum of its proper divisors (37273005).

66440787 is a wasteful number, since it uses less digits than its factorization.

66440787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77218.

The product of its (nonzero) digits is 225792, while the sum is 42.

The square root of 66440787 is about 8151.1218246325. The cubic root of 66440787 is about 405.0216662696.

The spelling of 66440787 in words is "sixty-six million, four hundred forty thousand, seven hundred eighty-seven".