249998891 has 8 divisors (see below), whose sum is σ = 261127680. Its totient is φ = 238891752.

The previous prime is 249998887. The next prime is 249998893. The reversal of 249998891 is 198899942.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 249998891 - 2² = 249998887 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 249998891.

It is not an unprimeable number, because it can be changed into a prime (249998893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20990 + ... + 30668.

It is an arithmetic number, because the mean of its divisors is an integer number (32640960).

Almost surely, 2^249998891 is an apocalyptic number.

249998891 is a deficient number, since it is larger than the sum of its proper divisors (11128789).

249998891 is a wasteful number, since it uses less digits than its factorization.

249998891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10825.

The product of its digits is 3359232, while the sum is 59.

The square root of 249998891 is about 15811.3532311438. The cubic root of 249998891 is about 629.9595934444.

The spelling of 249998891 in words is "two hundred forty-nine million, nine hundred ninety-eight thousand, eight hundred ninety-one".