249021 has 16 divisors (see below), whose sum is σ = 385920. Its totient is φ = 158400.

The previous prime is 249017. The next prime is 249037. The reversal of 249021 is 120942.

It is not a de Polignac number, because 249021 - 2² = 249017 is a prime.

It is a super-2 number, since 2×249021² = 124022916882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 248985 and 249003.

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 249021.

It is not an unprimeable number, because it can be changed into a prime (249421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 421 + ... + 821.

It is an arithmetic number, because the mean of its divisors is an integer number (24120).

2²⁴⁹⁰²¹ is an apocalyptic number.

It is an amenable number.

249021 is a deficient number, since it is larger than the sum of its proper divisors (136899).

249021 is a wasteful number, since it uses less digits than its factorization.

249021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 433 (or 427 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 249021 is about 499.0200396778. The cubic root of 249021 is about 62.9137140748.

Adding to 249021 its reverse (120942), we get a palindrome (369963).

It can be divided in two parts, 24 and 9021, that added together give a triangular number (9045 = T₁₃₄).

The spelling of 249021 in words is "two hundred forty-nine thousand, twenty-one".