249999879 has 4 divisors (see below), whose sum is σ = 333333176. Its totient is φ = 166666584.

The previous prime is 249999877. The next prime is 249999889. The reversal of 249999879 is 978999942.

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

It is not a de Polignac number, because 249999879 - 2¹ = 249999877 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 (249999877) 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, 41666644 + ... + 41666649.

It is an arithmetic number, because the mean of its divisors is an integer number (83333294).

Almost surely, 2^249999879 is an apocalyptic number.

249999879 is a deficient number, since it is larger than the sum of its proper divisors (83333297).

249999879 is an equidigital number, since it uses as much as digits as its factorization.

249999879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83333296.

The product of its digits is 26453952, while the sum is 66.

The square root of 249999879 is about 15811.3844744855. The cubic root of 249999879 is about 629.9604233138.

It can be divided in two parts, 2499 and 99879, that added together give a triangular number (102378 = T₄₅₂).

The spelling of 249999879 in words is "two hundred forty-nine million, nine hundred ninety-nine thousand, eight hundred seventy-nine".