73867561 has 2 divisors, whose sum is σ = 73867562. Its totient is φ = 73867560.

The previous prime is 73867517. The next prime is 73867579. The reversal of 73867561 is 16576837.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55591936 + 18275625 = 7456^2 + 4275^2 .

It is an emirp because it is prime and its reverse (16576837) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 73867561 - 2⁹ = 73867049 is a prime.

It is not a weakly prime, because it can be changed into another prime (73867501) 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, 36933780 + 36933781.

It is an arithmetic number, because the mean of its divisors is an integer number (36933781).

Almost surely, 2^73867561 is an apocalyptic number.

It is an amenable number.

73867561 is a deficient number, since it is larger than the sum of its proper divisors (1).

73867561 is an equidigital number, since it uses as much as digits as its factorization.

73867561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 211680, while the sum is 43.

The square root of 73867561 is about 8594.6239591968. The cubic root of 73867561 is about 419.5830347863.

The spelling of 73867561 in words is "seventy-three million, eight hundred sixty-seven thousand, five hundred sixty-one".