1248591779 has 4 divisors (see below), whose sum is σ = 1253950776. Its totient is φ = 1243232784.

The previous prime is 1248591749. The next prime is 1248591791. The reversal of 1248591779 is 9771958421.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1248591779 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 1248591779.

It is not an unprimeable number, because it can be changed into a prime (1248591749) 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, 2679149 + ... + 2679614.

It is an arithmetic number, because the mean of its divisors is an integer number (313487694).

Almost surely, 2^1248591779 is an apocalyptic number.

1248591779 is a deficient number, since it is larger than the sum of its proper divisors (5358997).

1248591779 is an equidigital number, since it uses as much as digits as its factorization.

1248591779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5358996.

The product of its digits is 1270080, while the sum is 53.

The square root of 1248591779 is about 35335.4181947801. The cubic root of 1248591779 is about 1076.8126703224.

The spelling of 1248591779 in words is "one billion, two hundred forty-eight million, five hundred ninety-one thousand, seven hundred seventy-nine".