73105561 has 2 divisors, whose sum is σ = 73105562. Its totient is φ = 73105560.

The previous prime is 73105553. The next prime is 73105601. The reversal of 73105561 is 16550137.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72999936 + 105625 = 8544^2 + 325^2 .

It is a cyclic number.

It is not a de Polignac number, because 73105561 - 2³ = 73105553 is a prime.

It is not a weakly prime, because it can be changed into another prime (73105541) 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, 36552780 + 36552781.

It is an arithmetic number, because the mean of its divisors is an integer number (36552781).

Almost surely, 2^73105561 is an apocalyptic number.

It is an amenable number.

73105561 is a deficient number, since it is larger than the sum of its proper divisors (1).

73105561 is an equidigital number, since it uses as much as digits as its factorization.

73105561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3150, while the sum is 28.

The square root of 73105561 is about 8550.1790039741. The cubic root of 73105561 is about 418.1352724888.

Adding to 73105561 its reverse (16550137), we get a palindrome (89655698).

The spelling of 73105561 in words is "seventy-three million, one hundred five thousand, five hundred sixty-one".