1309748285 has 4 divisors (see below), whose sum is σ = 1571697948. Its totient is φ = 1047798624.

The previous prime is 1309748281. The next prime is 1309748291. The reversal of 1309748285 is 5828479031.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5828479031 = 641 ⋅9092791.

It can be written as a sum of positive squares in 2 ways, for example, as 504721156 + 805027129 = 22466^2 + 28373^2 .

It is a cyclic number.

It is not a de Polignac number, because 1309748285 - 2² = 1309748281 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1309748281) 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, 130974824 + ... + 130974833.

It is an arithmetic number, because the mean of its divisors is an integer number (392924487).

Almost surely, 2^1309748285 is an apocalyptic number.

It is an amenable number.

1309748285 is a deficient number, since it is larger than the sum of its proper divisors (261949663).

1309748285 is an equidigital number, since it uses as much as digits as its factorization.

1309748285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261949662.

The product of its (nonzero) digits is 483840, while the sum is 47.

The square root of 1309748285 is about 36190.4446643033. Note that the first 3 decimals coincide. The cubic root of 1309748285 is about 1094.1140947951.

The spelling of 1309748285 in words is "one billion, three hundred nine million, seven hundred forty-eight thousand, two hundred eighty-five".