42505447 has 2 divisors, whose sum is σ = 42505448. Its totient is φ = 42505446.

The previous prime is 42505427. The next prime is 42505453. The reversal of 42505447 is 74450524.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42505447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42505427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21252723 + 21252724.

It is an arithmetic number, because the mean of its divisors is an integer number (21252724).

Almost surely, 2^42505447 is an apocalyptic number.

42505447 is a deficient number, since it is larger than the sum of its proper divisors (1).

42505447 is an equidigital number, since it uses as much as digits as its factorization.

42505447 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22400, while the sum is 31.

The square root of 42505447 is about 6519.6201576472. The cubic root of 42505447 is about 348.9915105364.

The spelling of 42505447 in words is "forty-two million, five hundred five thousand, four hundred forty-seven".