249889640 has 192 divisors, whose sum is σ = 764588160. Its totient is φ = 70986240.

The previous prime is 249889637. The next prime is 249889649. The reversal of 249889640 is 46988942.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249889649) 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 47 ways as a sum of consecutive naturals, for example, 3163121 + ... + 3163199.

It is an arithmetic number, because the mean of its divisors is an integer number (3982230).

Almost surely, 2^249889640 is an apocalyptic number.

249889640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 249889640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (382294080).

249889640 is an abundant number, since it is smaller than the sum of its proper divisors (514698520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

249889640 is a wasteful number, since it uses less digits than its factorization.

249889640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 50.

The square root of 249889640 is about 15807.8980259869. The cubic root of 249889640 is about 629.8678147127.

The spelling of 249889640 in words is "two hundred forty-nine million, eight hundred eighty-nine thousand, six hundred forty".