1309231 has 16 divisors (see below), whose sum is σ = 1670400. Its totient is φ = 1017240.

The previous prime is 1309219. The next prime is 1309237. The reversal of 1309231 is 1329031.

It is not a de Polignac number, because 1309231 - 2⁷ = 1309103 is a prime.

It is a super-2 number, since 2×1309231² = 3428171622722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1309199 and 1309208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1309237) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3600 + ... + 3946.

It is an arithmetic number, because the mean of its divisors is an integer number (104400).

2^1309231 is an apocalyptic number.

1309231 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1309231 is a deficient number, since it is larger than the sum of its proper divisors (361169).

1309231 is an equidigital number, since it uses as much as digits as its factorization.

1309231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 19.

The square root of 1309231 is about 1144.2163257007. The cubic root of 1309231 is about 109.3970035731.

It can be divided in two parts, 1309 and 231, that added together give a triangular number (1540 = T₅₅).

The spelling of 1309231 in words is "one million, three hundred nine thousand, two hundred thirty-one".