4019987 has 8 divisors (see below), whose sum is σ = 4193280. Its totient is φ = 3849480.

The previous prime is 4019909. The next prime is 4019993. The reversal of 4019987 is 7899104.

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

It is a cyclic number.

It is not a de Polignac number, because 4019987 - 2⁸ = 4019731 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 4019987.

It is not an unprimeable number, because it can be changed into a prime (4019387) 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 7 ways as a sum of consecutive naturals, for example, 2564 + ... + 3822.

It is an arithmetic number, because the mean of its divisors is an integer number (524160).

Almost surely, 2^4019987 is an apocalyptic number.

4019987 is a deficient number, since it is larger than the sum of its proper divisors (173293).

4019987 is a wasteful number, since it uses less digits than its factorization.

4019987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1393.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 4019987 is about 2004.9905236684. The cubic root of 4019987 is about 159.0040609171.

Adding to 4019987 its sum of digits (38), we get a square (4020025 = 2005²).

It can be divided in two parts, 40 and 19987, that multiplied together give a triangular number (799480 = T₁₂₆₄).

The spelling of 4019987 in words is "four million, nineteen thousand, nine hundred eighty-seven".