1306531 has 4 divisors (see below), whose sum is σ = 1309000. Its totient is φ = 1304064.

The previous prime is 1306519. The next prime is 1306541. The reversal of 1306531 is 1356031.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1356031 = 677 ⋅2003.

It is a cyclic number.

It is not a de Polignac number, because 1306531 - 2⁵ = 1306499 is a prime.

It is a super-2 number, since 2×1306531² = 3414046507922, 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 = 1306499 and 1306508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1306541) 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, 81 + ... + 1618.

It is an arithmetic number, because the mean of its divisors is an integer number (327250).

2^1306531 is an apocalyptic number.

1306531 is a deficient number, since it is larger than the sum of its proper divisors (2469).

1306531 is an equidigital number, since it uses as much as digits as its factorization.

1306531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2468.

The product of its (nonzero) digits is 270, while the sum is 19.

The square root of 1306531 is about 1143.0358699533. The cubic root of 1306531 is about 109.3217494254.

The spelling of 1306531 in words is "one million, three hundred six thousand, five hundred thirty-one".