12191901 has 16 divisors (see below), whose sum is σ = 17280000. Its totient is φ = 7624368.

The previous prime is 12191899. The next prime is 12191903. The reversal of 12191901 is 10919121.

It is an interprime number because it is at equal distance from previous prime (12191899) and next prime (12191903).

It is not a de Polignac number, because 12191901 - 2¹ = 12191899 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12191903) 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 15 ways as a sum of consecutive naturals, for example, 5100 + ... + 7098.

It is an arithmetic number, because the mean of its divisors is an integer number (1080000).

Almost surely, 2^12191901 is an apocalyptic number.

It is an amenable number.

12191901 is a deficient number, since it is larger than the sum of its proper divisors (5088099).

12191901 is a wasteful number, since it uses less digits than its factorization.

12191901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2128.

The product of its (nonzero) digits is 162, while the sum is 24.

The square root of 12191901 is about 3491.6902783609. The cubic root of 12191901 is about 230.1567991923.

The spelling of 12191901 in words is "twelve million, one hundred ninety-one thousand, nine hundred one".