249766139 has 4 divisors (see below), whose sum is σ = 285447024. Its totient is φ = 214085256.

The previous prime is 249766133. The next prime is 249766171. The reversal of 249766139 is 931667942.

It is a happy number.

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

It is not a de Polignac number, because 249766139 - 2⁴ = 249766123 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 249766093 and 249766102.

It is not an unprimeable number, because it can be changed into a prime (249766133) 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, 17840432 + ... + 17840445.

It is an arithmetic number, because the mean of its divisors is an integer number (71361756).

Almost surely, 2^249766139 is an apocalyptic number.

249766139 is a deficient number, since it is larger than the sum of its proper divisors (35680885).

249766139 is an equidigital number, since it uses as much as digits as its factorization.

249766139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35680884.

The product of its digits is 489888, while the sum is 47.

The square root of 249766139 is about 15803.9912363934. The cubic root of 249766139 is about 629.7640327344.

The spelling of 249766139 in words is "two hundred forty-nine million, seven hundred sixty-six thousand, one hundred thirty-nine".