4198921 has 2 divisors, whose sum is σ = 4198922. Its totient is φ = 4198920.

The previous prime is 4198891. The next prime is 4198927. The reversal of 4198921 is 1298914.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2758921 + 1440000 = 1661^2 + 1200^2 .

It is a cyclic number.

It is not a de Polignac number, because 4198921 - 2⁵ = 4198889 is a prime.

4198921 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (4198927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2099460 + 2099461.

It is an arithmetic number, because the mean of its divisors is an integer number (2099461).

Almost surely, 2^4198921 is an apocalyptic number.

It is an amenable number.

4198921 is a deficient number, since it is larger than the sum of its proper divisors (1).

4198921 is an equidigital number, since it uses as much as digits as its factorization.

4198921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 34.

The square root of 4198921 is about 2049.1268872376. The cubic root of 4198921 is about 161.3290468357.

The spelling of 4198921 in words is "four million, one hundred ninety-eight thousand, nine hundred twenty-one".