1249749749 has 4 divisors (see below), whose sum is σ = 1253525760. Its totient is φ = 1245973740.

The previous prime is 1249749737. The next prime is 1249749763. The reversal of 1249749749 is 9479479421.

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 not a de Polignac number, because 1249749749 - 2²⁸ = 981314293 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1249749694 and 1249749703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1249749769) 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, 1887509 + ... + 1888170.

It is an arithmetic number, because the mean of its divisors is an integer number (313381440).

Almost surely, 2^1249749749 is an apocalyptic number.

It is an amenable number.

1249749749 is a deficient number, since it is larger than the sum of its proper divisors (3776011).

1249749749 is an equidigital number, since it uses as much as digits as its factorization.

1249749749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3776010.

The product of its digits is 4572288, while the sum is 56.

The square root of 1249749749 is about 35351.7997985958. The cubic root of 1249749749 is about 1077.1454536267.

The spelling of 1249749749 in words is "one billion, two hundred forty-nine million, seven hundred forty-nine thousand, seven hundred forty-nine".