42425809 has 2 divisors, whose sum is σ = 42425810. Its totient is φ = 42425808.

The previous prime is 42425797. The next prime is 42425827. The reversal of 42425809 is 90852424.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40259025 + 2166784 = 6345^2 + 1472^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42425809 is a prime.

It is not a weakly prime, because it can be changed into another prime (42425609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21212904 + 21212905.

It is an arithmetic number, because the mean of its divisors is an integer number (21212905).

Almost surely, 2^42425809 is an apocalyptic number.

It is an amenable number.

42425809 is a deficient number, since it is larger than the sum of its proper divisors (1).

42425809 is an equidigital number, since it uses as much as digits as its factorization.

42425809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23040, while the sum is 34.

The square root of 42425809 is about 6513.5097297847. The cubic root of 42425809 is about 348.7734180050.

It can be divided in two parts, 42425 and 809, that added together give a palindrome (43234).

The spelling of 42425809 in words is "forty-two million, four hundred twenty-five thousand, eight hundred nine".