42505787 has 2 divisors, whose sum is σ = 42505788. Its totient is φ = 42505786.

The previous prime is 42505781. The next prime is 42505819. The reversal of 42505787 is 78750524.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42505787 - 2¹² = 42501691 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42505787.

It is not a weakly prime, because it can be changed into another prime (42505781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21252893 + 21252894.

It is an arithmetic number, because the mean of its divisors is an integer number (21252894).

Almost surely, 2^42505787 is an apocalyptic number.

42505787 is a deficient number, since it is larger than the sum of its proper divisors (1).

42505787 is an equidigital number, since it uses as much as digits as its factorization.

42505787 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 78400, while the sum is 38.

The square root of 42505787 is about 6519.6462327338. The cubic root of 42505787 is about 348.9924410587.

The spelling of 42505787 in words is "forty-two million, five hundred five thousand, seven hundred eighty-seven".