73003561 has 4 divisors (see below), whose sum is σ = 73040724. Its totient is φ = 72966400.

The previous prime is 73003547. The next prime is 73003573. The reversal of 73003561 is 16530037.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16530037 = 31 ⋅533227.

It can be written as a sum of positive squares in 2 ways, for example, as 46840336 + 26163225 = 6844^2 + 5115^2 .

It is a cyclic number.

It is not a de Polignac number, because 73003561 - 2⁷ = 73003433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (73003501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15460 + ... + 19621.

It is an arithmetic number, because the mean of its divisors is an integer number (18260181).

Almost surely, 2^73003561 is an apocalyptic number.

It is an amenable number.

73003561 is a deficient number, since it is larger than the sum of its proper divisors (37163).

73003561 is a wasteful number, since it uses less digits than its factorization.

73003561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37162.

The product of its (nonzero) digits is 1890, while the sum is 25.

The square root of 73003561 is about 8544.2121345388. The cubic root of 73003561 is about 417.9407152477.

Adding to 73003561 its reverse (16530037), we get a palindrome (89533598).

The spelling of 73003561 in words is "seventy-three million, three thousand, five hundred sixty-one".