42565091 has 2 divisors, whose sum is σ = 42565092. Its totient is φ = 42565090.

The previous prime is 42565079. The next prime is 42565109. The reversal of 42565091 is 19056524.

It is a happy number.

Together with next prime (42565109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42565091 - 2¹⁸ = 42302947 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (42565031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21282545 + 21282546.

It is an arithmetic number, because the mean of its divisors is an integer number (21282546).

Almost surely, 2^42565091 is an apocalyptic number.

42565091 is a deficient number, since it is larger than the sum of its proper divisors (1).

42565091 is an equidigital number, since it uses as much as digits as its factorization.

42565091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 42565091 is about 6524.1927469994. The cubic root of 42565091 is about 349.1546701835.

The spelling of 42565091 in words is "forty-two million, five hundred sixty-five thousand, ninety-one".