42047561 has 2 divisors, whose sum is σ = 42047562. Its totient is φ = 42047560.

The previous prime is 42047539. The next prime is 42047569. The reversal of 42047561 is 16574024.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25441936 + 16605625 = 5044^2 + 4075^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42047561 is a prime.

It is not a weakly prime, because it can be changed into another prime (42047569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21023780 + 21023781.

It is an arithmetic number, because the mean of its divisors is an integer number (21023781).

Almost surely, 2^42047561 is an apocalyptic number.

It is an amenable number.

42047561 is a deficient number, since it is larger than the sum of its proper divisors (1).

42047561 is an equidigital number, since it uses as much as digits as its factorization.

42047561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 42047561 is about 6484.4090709948. The cubic root of 42047561 is about 347.7338239634.

The spelling of 42047561 in words is "forty-two million, forty-seven thousand, five hundred sixty-one".