16861987 has 8 divisors (see below), whose sum is σ = 17787600. Its totient is φ = 15940224.

The previous prime is 16861981. The next prime is 16861991. The reversal of 16861987 is 78916861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16861987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16861981) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14823 + ... + 15919.

It is an arithmetic number, because the mean of its divisors is an integer number (2223450).

Almost surely, 2^16861987 is an apocalyptic number.

16861987 is a deficient number, since it is larger than the sum of its proper divisors (925613).

16861987 is a wasteful number, since it uses less digits than its factorization.

16861987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1925.

The product of its digits is 145152, while the sum is 46.

The square root of 16861987 is about 4106.3349838999. The cubic root of 16861987 is about 256.4304434408.

The spelling of 16861987 in words is "sixteen million, eight hundred sixty-one thousand, nine hundred eighty-seven".