13531309 has 6 divisors (see below), whose sum is σ = 14873390. Its totient is φ = 12301080.

The previous prime is 13531277. The next prime is 13531319. The reversal of 13531309 is 90313531.

It can be written as a sum of positive squares in only one way, i.e., 12938409 + 592900 = 3597^2 + 770^2 .

It is not a de Polignac number, because 13531309 - 2⁵ = 13531277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13531319) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55794 + ... + 56035.

Almost surely, 2^13531309 is an apocalyptic number.

It is an amenable number.

13531309 is a deficient number, since it is larger than the sum of its proper divisors (1342081).

13531309 is a wasteful number, since it uses less digits than its factorization.

13531309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111851 (or 111840 counting only the distinct ones).

The product of its (nonzero) digits is 1215, while the sum is 25.

The square root of 13531309 is about 3678.4927619883. The cubic root of 13531309 is about 238.2940895280.

It can be divided in two parts, 1353 and 1309, that added together give a palindrome (2662).

The spelling of 13531309 in words is "thirteen million, five hundred thirty-one thousand, three hundred nine".