1248749785 has 4 divisors (see below), whose sum is σ = 1498499748. Its totient is φ = 998999824.

The previous prime is 1248749783. The next prime is 1248749797. The reversal of 1248749785 is 5879478421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5879478421 = 109 ⋅53940169.

It can be written as a sum of positive squares in 2 ways, for example, as 821624896 + 427124889 = 28664^2 + 20667^2 .

It is a cyclic number.

It is not a de Polignac number, because 1248749785 - 2¹ = 1248749783 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1248749783) 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, 124874974 + ... + 124874983.

It is an arithmetic number, because the mean of its divisors is an integer number (374624937).

Almost surely, 2^1248749785 is an apocalyptic number.

It is an amenable number.

1248749785 is a deficient number, since it is larger than the sum of its proper divisors (249749963).

1248749785 is an equidigital number, since it uses as much as digits as its factorization.

1248749785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249749962.

The product of its digits is 4515840, while the sum is 55.

The square root of 1248749785 is about 35337.6539260885. The cubic root of 1248749785 is about 1076.8580910086.

The spelling of 1248749785 in words is "one billion, two hundred forty-eight million, seven hundred forty-nine thousand, seven hundred eighty-five".