42502561 has 2 divisors, whose sum is σ = 42502562. Its totient is φ = 42502560.

The previous prime is 42502549. The next prime is 42502591. The reversal of 42502561 is 16520524.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31979025 + 10523536 = 5655^2 + 3244^2 .

It is a cyclic number.

It is not a de Polignac number, because 42502561 - 2¹⁷ = 42371489 is a prime.

It is not a weakly prime, because it can be changed into another prime (42502501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21251280 + 21251281.

It is an arithmetic number, because the mean of its divisors is an integer number (21251281).

Almost surely, 2^42502561 is an apocalyptic number.

It is an amenable number.

42502561 is a deficient number, since it is larger than the sum of its proper divisors (1).

42502561 is an equidigital number, since it uses as much as digits as its factorization.

42502561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 42502561 is about 6519.3988219774. The cubic root of 42502561 is about 348.9836118445.

The spelling of 42502561 in words is "forty-two million, five hundred two thousand, five hundred sixty-one".