16939987 has 4 divisors (see below), whose sum is σ = 17038080. Its totient is φ = 16841896.

The previous prime is 16939933. The next prime is 16939997. The reversal of 16939987 is 78993961.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78993961 = 71 ⋅1112591.

It is not a de Polignac number, because 16939987 - 2¹¹ = 16937939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16939907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48787 + ... + 49132.

It is an arithmetic number, because the mean of its divisors is an integer number (4259520).

Almost surely, 2^16939987 is an apocalyptic number.

16939987 is a deficient number, since it is larger than the sum of its proper divisors (98093).

16939987 is an equidigital number, since it uses as much as digits as its factorization.

16939987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98092.

The product of its digits is 734832, while the sum is 52.

The square root of 16939987 is about 4115.8215461801. The cubic root of 16939987 is about 256.8252330659.

The spelling of 16939987 in words is "sixteen million, nine hundred thirty-nine thousand, nine hundred eighty-seven".