249979879 has 4 divisors (see below), whose sum is σ = 250458376. Its totient is φ = 249501384.

The previous prime is 249979871. The next prime is 249979909. The reversal of 249979879 is 978979942.

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

It is a cyclic number.

It is not a de Polignac number, because 249979879 - 2³ = 249979871 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 249979879.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249979871) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 238464 + ... + 239509.

It is an arithmetic number, because the mean of its divisors is an integer number (62614594).

Almost surely, 2^249979879 is an apocalyptic number.

249979879 is a deficient number, since it is larger than the sum of its proper divisors (478497).

249979879 is an equidigital number, since it uses as much as digits as its factorization.

249979879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478496.

The product of its digits is 20575296, while the sum is 64.

The square root of 249979879 is about 15810.7520061508. The cubic root of 249979879 is about 629.9436239130.

The spelling of 249979879 in words is "two hundred forty-nine million, nine hundred seventy-nine thousand, eight hundred seventy-nine".