249987 has 8 divisors (see below), whose sum is σ = 347904. Its totient is φ = 159368.

The previous prime is 249973. The next prime is 249989. The reversal of 249987 is 789942.

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 249987 - 2⁴ = 249971 is a prime.

It is a d-powerful number, because it can be written as 2¹⁷ + 4² + 9 + 9³ + 8³ + 7⁶ .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 249987.

It is not an unprimeable number, because it can be changed into a prime (249989) 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, 1743 + ... + 1880.

It is an arithmetic number, because the mean of its divisors is an integer number (43488).

2²⁴⁹⁹⁸⁷ is an apocalyptic number.

249987 is a deficient number, since it is larger than the sum of its proper divisors (97917).

249987 is a wasteful number, since it uses less digits than its factorization.

249987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3649.

The product of its digits is 36288, while the sum is 39.

The square root of 249987 is about 499.9869998310. The cubic root of 249987 is about 62.9949605442.

It can be divided in two parts, 24 and 9987, that added together give a triangular number (10011 = T₁₄₁).

The spelling of 249987 in words is "two hundred forty-nine thousand, nine hundred eighty-seven".