41721209 has 2 divisors, whose sum is σ = 41721210. Its totient is φ = 41721208.

The previous prime is 41721193. The next prime is 41721259. The reversal of 41721209 is 90212714.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41538025 + 183184 = 6445^2 + 428^2 .

It is a cyclic number.

It is not a de Polignac number, because 41721209 - 2⁴ = 41721193 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is equal to p_2531780 and since 41721209 and 2531780 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (41721259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20860604 + 20860605.

It is an arithmetic number, because the mean of its divisors is an integer number (20860605).

Almost surely, 2^41721209 is an apocalyptic number.

It is an amenable number.

41721209 is a deficient number, since it is larger than the sum of its proper divisors (1).

41721209 is an equidigital number, since it uses as much as digits as its factorization.

41721209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 41721209 is about 6459.1956929636. The cubic root of 41721209 is about 346.8318413852.

The spelling of 41721209 in words is "forty-one million, seven hundred twenty-one thousand, two hundred nine".