1248849809 has 4 divisors (see below), whose sum is σ = 1257834480. Its totient is φ = 1239865140.

The previous prime is 1248849779. The next prime is 1248849821. The reversal of 1248849809 is 9089488421.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1248849809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1248849839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4492127 + ... + 4492404.

It is an arithmetic number, because the mean of its divisors is an integer number (314458620).

Almost surely, 2^1248849809 is an apocalyptic number.

It is an amenable number.

1248849809 is a deficient number, since it is larger than the sum of its proper divisors (8984671).

1248849809 is an equidigital number, since it uses as much as digits as its factorization.

1248849809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8984670.

The product of its (nonzero) digits is 1327104, while the sum is 53.

The square root of 1248849809 is about 35339.0691586522. The cubic root of 1248849809 is about 1076.8868421054.

The spelling of 1248849809 in words is "one billion, two hundred forty-eight million, eight hundred forty-nine thousand, eight hundred nine".