16042561 has 2 divisors, whose sum is σ = 16042562. Its totient is φ = 16042560.

The previous prime is 16042549. The next prime is 16042567. The reversal of 16042561 is 16524061.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9120400 + 6922161 = 3020^2 + 2631^2 .

It is a cyclic number.

It is not a de Polignac number, because 16042561 - 2⁵ = 16042529 is a prime.

It is not a weakly prime, because it can be changed into another prime (16042567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8021280 + 8021281.

It is an arithmetic number, because the mean of its divisors is an integer number (8021281).

Almost surely, 2^16042561 is an apocalyptic number.

It is an amenable number.

16042561 is a deficient number, since it is larger than the sum of its proper divisors (1).

16042561 is an equidigital number, since it uses as much as digits as its factorization.

16042561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 16042561 is about 4005.3165917315. The cubic root of 16042561 is about 252.2074434067.

The spelling of 16042561 in words is "sixteen million, forty-two thousand, five hundred sixty-one".