12197921 has 2 divisors, whose sum is σ = 12197922. Its totient is φ = 12197920.

The previous prime is 12197917. The next prime is 12197947. The reversal of 12197921 is 12979121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7639696 + 4558225 = 2764^2 + 2135^2 .

It is a cyclic number.

It is not a de Polignac number, because 12197921 - 2² = 12197917 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12197971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6098960 + 6098961.

It is an arithmetic number, because the mean of its divisors is an integer number (6098961).

Almost surely, 2^12197921 is an apocalyptic number.

It is an amenable number.

12197921 is a deficient number, since it is larger than the sum of its proper divisors (1).

12197921 is an equidigital number, since it uses as much as digits as its factorization.

12197921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2268, while the sum is 32.

The square root of 12197921 is about 3492.5522186504. The cubic root of 12197921 is about 230.1946744984.

The spelling of 12197921 in words is "twelve million, one hundred ninety-seven thousand, nine hundred twenty-one".