73998181 has 4 divisors (see below), whose sum is σ = 74015500. Its totient is φ = 73980864.

The previous prime is 73998173. The next prime is 73998193. The reversal of 73998181 is 18189937.

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.

It can be written as a sum of positive squares in 2 ways, for example, as 40832100 + 33166081 = 6390^2 + 5759^2 .

It is a cyclic number.

It is not a de Polignac number, because 73998181 - 2³ = 73998173 is a prime.

It is a super-2 number, since 2×73998181² = 10951461582617522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73992181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2845 + ... + 12493.

It is an arithmetic number, because the mean of its divisors is an integer number (18503875).

Almost surely, 2^73998181 is an apocalyptic number.

It is an amenable number.

73998181 is a deficient number, since it is larger than the sum of its proper divisors (17319).

73998181 is an equidigital number, since it uses as much as digits as its factorization.

73998181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17318.

The product of its digits is 108864, while the sum is 46.

The square root of 73998181 is about 8602.2195391655. The cubic root of 73998181 is about 419.8302053644.

The spelling of 73998181 in words is "seventy-three million, nine hundred ninety-eight thousand, one hundred eighty-one".