249997820 has 48 divisors (see below), whose sum is σ = 563099040. Its totient is φ = 92941056.

The previous prime is 249997819. The next prime is 249997843. The reversal of 249997820 is 28799942.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13934 + ... + 26346.

It is an arithmetic number, because the mean of its divisors is an integer number (11731230).

Almost surely, 2^249997820 is an apocalyptic number.

249997820 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 249997820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (281549520).

249997820 is an abundant number, since it is smaller than the sum of its proper divisors (313101220).

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

249997820 is a wasteful number, since it uses less digits than its factorization.

249997820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12494 (or 12492 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 50.

The square root of 249997820 is about 15811.3193630386. The cubic root of 249997820 is about 629.9586938569.

The spelling of 249997820 in words is "two hundred forty-nine million, nine hundred ninety-seven thousand, eight hundred twenty".