73633561 has 3 divisors (see below), whose sum is σ = 73642143. Its totient is φ = 73624980.

The previous prime is 73633541. The next prime is 73633583. The reversal of 73633561 is 16533637.

The square root of 73633561 is 8581.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 16533637 = 757 ⋅21841.

It can be written as a sum of positive squares in only one way, i.e., 17161 + 73616400 = 131^2 + 8580^2 .

It is not a de Polignac number, because 73633561 - 2¹⁷ = 73502489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (73633541) 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 2 ways as a sum of consecutive naturals, for example, 4291 + ... + 12871.

It is an arithmetic number, because the mean of its divisors is an integer number (24547381).

Almost surely, 2^73633561 is an apocalyptic number.

73633561 is the 8581-st square number.

73633561 is the 4291-st centered octagonal number.

It is an amenable number.

73633561 is a deficient number, since it is larger than the sum of its proper divisors (8582).

73633561 is an frugal number, since it uses more digits than its factorization.

73633561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17162 (or 8581 counting only the distinct ones).

The product of its digits is 34020, while the sum is 34.

The cubic root of 73633561 is about 419.1395099752.

The spelling of 73633561 in words is "seventy-three million, six hundred thirty-three thousand, five hundred sixty-one".