12140391 has 4 divisors (see below), whose sum is σ = 16187192. Its totient is φ = 8093592.

The previous prime is 12140353. The next prime is 12140419. The reversal of 12140391 is 19304121.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 12140391 - 2¹⁸ = 11878247 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 (12140341) 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, 2023396 + ... + 2023401.

It is an arithmetic number, because the mean of its divisors is an integer number (4046798).

Almost surely, 2^12140391 is an apocalyptic number.

12140391 is a deficient number, since it is larger than the sum of its proper divisors (4046801).

12140391 is an equidigital number, since it uses as much as digits as its factorization.

12140391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4046800.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 12140391 is about 3484.3063872168. The cubic root of 12140391 is about 229.8322090649.

The spelling of 12140391 in words is "twelve million, one hundred forty thousand, three hundred ninety-one".