249711 has 32 divisors (see below), whose sum is σ = 442368. Its totient is φ = 121440.

The previous prime is 249703. The next prime is 249721. The reversal of 249711 is 117942.

Added to its reverse (117942) it gives a triangular number (367653 = T₈₅₇).

It is not a de Polignac number, because 249711 - 2³ = 249703 is a prime.

It is an Ulam number.

249711 is a lucky 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 249711.

It is not an unprimeable number, because it can be changed into a prime (249721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5290 + ... + 5336.

It is an arithmetic number, because the mean of its divisors is an integer number (13824).

2²⁴⁹⁷¹¹ is an apocalyptic number.

249711 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

249711 is a deficient number, since it is larger than the sum of its proper divisors (192657).

249711 is a wasteful number, since it uses less digits than its factorization.

249711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91.

The product of its digits is 504, while the sum is 24.

The square root of 249711 is about 499.7109164307. The cubic root of 249711 is about 62.9717686561.

Adding to 249711 its reverse (117942), we get a triangular number (367653 = T₈₅₇).

Subtracting from 249711 its reverse (117942), we obtain a square (131769 = 363²).

The spelling of 249711 in words is "two hundred forty-nine thousand, seven hundred eleven".