249999797 has 4 divisors (see below), whose sum is σ = 250642860. Its totient is φ = 249356736.

The previous prime is 249999793. The next prime is 249999809. The reversal of 249999797 is 797999942.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 134351281 + 115648516 = 11591^2 + 10754^2 .

It is a cyclic number.

It is not a de Polignac number, because 249999797 - 2² = 249999793 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249999793) 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 3 ways as a sum of consecutive naturals, for example, 320948 + ... + 321725.

It is an arithmetic number, because the mean of its divisors is an integer number (62660715).

Almost surely, 2^249999797 is an apocalyptic number.

It is an amenable number.

249999797 is a deficient number, since it is larger than the sum of its proper divisors (643063).

249999797 is an equidigital number, since it uses as much as digits as its factorization.

249999797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 643062.

The product of its digits is 23147208, while the sum is 65.

The square root of 249999797 is about 15811.3818814169. The cubic root of 249999797 is about 629.9603544381.

The spelling of 249999797 in words is "two hundred forty-nine million, nine hundred ninety-nine thousand, seven hundred ninety-seven".