12149921 has 4 divisors (see below), whose sum is σ = 13885632. Its totient is φ = 10414212.

The previous prime is 12149881. The next prime is 12149933. The reversal of 12149921 is 12994121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12994121 = 7 ⋅1856303.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12149921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12149941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 867845 + ... + 867858.

It is an arithmetic number, because the mean of its divisors is an integer number (3471408).

Almost surely, 2^12149921 is an apocalyptic number.

It is an amenable number.

12149921 is a deficient number, since it is larger than the sum of its proper divisors (1735711).

12149921 is an equidigital number, since it uses as much as digits as its factorization.

12149921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1735710.

The product of its digits is 1296, while the sum is 29.

The square root of 12149921 is about 3485.6736795059. The cubic root of 12149921 is about 229.8923314582.

The spelling of 12149921 in words is "twelve million, one hundred forty-nine thousand, nine hundred twenty-one".