66016987 has 4 divisors (see below), whose sum is σ = 66042000. Its totient is φ = 65991976.

The previous prime is 66016981. The next prime is 66017023. The reversal of 66016987 is 78961066.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66016987 - 2⁷ = 66016859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66016981) 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 3 ways as a sum of consecutive naturals, for example, 8008 + ... + 14005.

It is an arithmetic number, because the mean of its divisors is an integer number (16510500).

Almost surely, 2^66016987 is an apocalyptic number.

66016987 is a deficient number, since it is larger than the sum of its proper divisors (25013).

66016987 is a wasteful number, since it uses less digits than its factorization.

66016987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25012.

The product of its (nonzero) digits is 108864, while the sum is 43.

The square root of 66016987 is about 8125.0838149523. The cubic root of 66016987 is about 404.1586700701.

The spelling of 66016987 in words is "sixty-six million, sixteen thousand, nine hundred eighty-seven".