42017309 has 2 divisors, whose sum is σ = 42017310. Its totient is φ = 42017308.

The previous prime is 42017291. The next prime is 42017329. The reversal of 42017309 is 90371024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21132409 + 20884900 = 4597^2 + 4570^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42017309 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_2548610 and since 42017309 and 2548610 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42017329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21008654 + 21008655.

It is an arithmetic number, because the mean of its divisors is an integer number (21008655).

Almost surely, 2^42017309 is an apocalyptic number.

It is an amenable number.

42017309 is a deficient number, since it is larger than the sum of its proper divisors (1).

42017309 is an equidigital number, since it uses as much as digits as its factorization.

42017309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 42017309 is about 6482.0759791906. The cubic root of 42017309 is about 347.6504091568.

The spelling of 42017309 in words is "forty-two million, seventeen thousand, three hundred nine".