42544309 has 2 divisors, whose sum is σ = 42544310. Its totient is φ = 42544308.

The previous prime is 42544303. The next prime is 42544343. The reversal of 42544309 is 90344524.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25979409 + 16564900 = 5097^2 + 4070^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42544309 is a prime.

It is a Chen prime.

It is equal to p_2578702 and since 42544309 and 2578702 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 (42544303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21272154 + 21272155.

It is an arithmetic number, because the mean of its divisors is an integer number (21272155).

Almost surely, 2^42544309 is an apocalyptic number.

It is an amenable number.

42544309 is a deficient number, since it is larger than the sum of its proper divisors (1).

42544309 is an equidigital number, since it uses as much as digits as its factorization.

42544309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 42544309 is about 6522.5998650845. The cubic root of 42544309 is about 349.0978371198.

The spelling of 42544309 in words is "forty-two million, five hundred forty-four thousand, three hundred nine".