12021291 has 10 divisors (see below), whose sum is σ = 17957852. Its totient is φ = 8014140.

The previous prime is 12021287. The next prime is 12021299. The reversal of 12021291 is 19212021.

It is not a de Polignac number, because 12021291 - 2² = 12021287 is a prime.

It is a super-2 number, since 2×12021291² = 289022874613362, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12021299) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 74125 + ... + 74286.

Almost surely, 2^12021291 is an apocalyptic number.

12021291 is a deficient number, since it is larger than the sum of its proper divisors (5936561).

12021291 is an equidigital number, since it uses as much as digits as its factorization.

12021291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148423 (or 148414 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 12021291 is about 3467.1733443830. The cubic root of 12021291 is about 229.0781691276.

The spelling of 12021291 in words is "twelve million, twenty-one thousand, two hundred ninety-one".