12091531 has 4 divisors (see below), whose sum is σ = 12099592. Its totient is φ = 12083472.

The previous prime is 12091517. The next prime is 12091559. The reversal of 12091531 is 13519021.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 12091531 - 2⁹ = 12091019 is a prime.

It is a super-2 number, since 2×12091531² = 292410243847922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12091571) 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, 1041 + ... + 5026.

It is an arithmetic number, because the mean of its divisors is an integer number (3024898).

Almost surely, 2^12091531 is an apocalyptic number.

12091531 is a deficient number, since it is larger than the sum of its proper divisors (8061).

12091531 is an equidigital number, since it uses as much as digits as its factorization.

12091531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8060.

The product of its (nonzero) digits is 270, while the sum is 22.

The square root of 12091531 is about 3477.2878799432. The cubic root of 12091531 is about 229.5234683133.

The spelling of 12091531 in words is "twelve million, ninety-one thousand, five hundred thirty-one".