42785909 has 2 divisors, whose sum is σ = 42785910. Its totient is φ = 42785908.

The previous prime is 42785887. The next prime is 42785959. The reversal of 42785909 is 90958724.

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., 41088100 + 1697809 = 6410^2 + 1303^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42785909 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42785909.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42785959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21392954 + 21392955.

It is an arithmetic number, because the mean of its divisors is an integer number (21392955).

Almost surely, 2^42785909 is an apocalyptic number.

It is an amenable number.

42785909 is a deficient number, since it is larger than the sum of its proper divisors (1).

42785909 is an equidigital number, since it uses as much as digits as its factorization.

42785909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 44.

The square root of 42785909 is about 6541.0938687654. The cubic root of 42785909 is about 349.7574074029.

The spelling of 42785909 in words is "forty-two million, seven hundred eighty-five thousand, nine hundred nine".