1309861 has 4 divisors (see below), whose sum is σ = 1496992. Its totient is φ = 1122732.

The previous prime is 1309849. The next prime is 1309877. The reversal of 1309861 is 1689031.

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 not a de Polignac number, because 1309861 - 2⁵ = 1309829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1309801) 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, 93555 + ... + 93568.

It is an arithmetic number, because the mean of its divisors is an integer number (374248).

2^1309861 is an apocalyptic number.

It is an amenable number.

1309861 is a deficient number, since it is larger than the sum of its proper divisors (187131).

1309861 is an equidigital number, since it uses as much as digits as its factorization.

1309861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187130.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 1309861 is about 1144.4915901832. The cubic root of 1309861 is about 109.4145479842.

The spelling of 1309861 in words is "one million, three hundred nine thousand, eight hundred sixty-one".