17996987 has 2 divisors, whose sum is σ = 17996988. Its totient is φ = 17996986.

The previous prime is 17996983. The next prime is 17997037. The reversal of 17996987 is 78969971.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 17996987 - 2² = 17996983 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (17996981) 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 as a sum of consecutive naturals, namely, 8998493 + 8998494.

It is an arithmetic number, because the mean of its divisors is an integer number (8998494).

Almost surely, 2^17996987 is an apocalyptic number.

17996987 is a deficient number, since it is larger than the sum of its proper divisors (1).

17996987 is an equidigital number, since it uses as much as digits as its factorization.

17996987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1714608, while the sum is 56.

The square root of 17996987 is about 4242.2855868034. The cubic root of 17996987 is about 262.0595158386.

The spelling of 17996987 in words is "seventeen million, nine hundred ninety-six thousand, nine hundred eighty-seven".