1309873 has 4 divisors (see below), whose sum is σ = 1366848. Its totient is φ = 1252900.

The previous prime is 1309849. The next prime is 1309877. The reversal of 1309873 is 3789031.

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, and also an emirpimes, since its reverse is a distinct semiprime: 3789031 = 43 ⋅88117.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1309873 is a prime.

It is a super-2 number, since 2×1309873² = 3431534552258, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1309877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28453 + ... + 28498.

It is an arithmetic number, because the mean of its divisors is an integer number (341712).

2^1309873 is an apocalyptic number.

It is an amenable number.

1309873 is a deficient number, since it is larger than the sum of its proper divisors (56975).

1309873 is an equidigital number, since it uses as much as digits as its factorization.

1309873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56974.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 1309873 is about 1144.4968326736. The cubic root of 1309873 is about 109.4148821088.

The spelling of 1309873 in words is "one million, three hundred nine thousand, eight hundred seventy-three".