249381 has 18 divisors (see below), whose sum is σ = 397670. Its totient is φ = 150480.

The previous prime is 249377. The next prime is 249383. The reversal of 249381 is 183942.

It can be written as a sum of positive squares in only one way, i.e., 245025 + 4356 = 495^2 + 66^2 .

It is not a de Polignac number, because 249381 - 2² = 249377 is a prime.

It is a super-2 number, since 2×249381² = 124381766322, which contains 22 as substring.

It is a d-powerful number, because it can be written as 2⁷ + 4⁸ + 3¹¹ + 9⁴ + 8 + 1 .

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 249381.

It is not an unprimeable number, because it can be changed into a prime (249383) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 975 + ... + 1203.

2²⁴⁹³⁸¹ is an apocalyptic number.

It is an amenable number.

249381 is a deficient number, since it is larger than the sum of its proper divisors (148289).

249381 is a wasteful number, since it uses less digits than its factorization.

249381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257 (or 243 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 249381 is about 499.3806163639. The cubic root of 249381 is about 62.9440167823.

It can be divided in two parts, 249 and 381, that added together give a triangular number (630 = T₃₅).

The spelling of 249381 in words is "two hundred forty-nine thousand, three hundred eighty-one".