249491808 has 72 divisors (see below), whose sum is σ = 719272008. Its totient is φ = 82017792.

The previous prime is 249491773. The next prime is 249491819. The reversal of 249491808 is 808194942.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15091 + ... + 26957.

It is an arithmetic number, because the mean of its divisors is an integer number (9989889).

Almost surely, 2^249491808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 249491808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (359636004).

249491808 is an abundant number, since it is smaller than the sum of its proper divisors (469780200).

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

249491808 is a wasteful number, since it uses less digits than its factorization.

249491808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11956 (or 11945 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The square root of 249491808 is about 15795.3096835738. The cubic root of 249491808 is about 629.5333808562.

The spelling of 249491808 in words is "two hundred forty-nine million, four hundred ninety-one thousand, eight hundred eight".