73218520 has 64 divisors (see below), whose sum is σ = 168933600. Its totient is φ = 28554240.

The previous prime is 73218511. The next prime is 73218539. The reversal of 73218520 is 2581237.

It is a plaindrome in base 13.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 466282 + ... + 466438.

Almost surely, 2^73218520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 73218520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84466800).

73218520 is an abundant number, since it is smaller than the sum of its proper divisors (95715080).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

73218520 is a wasteful number, since it uses less digits than its factorization.

73218520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388 (or 384 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 73218520 is about 8556.7821054413. The cubic root of 73218520 is about 418.3505221249.

Adding to 73218520 its reverse (2581237), we get a palindrome (75799757).

The spelling of 73218520 in words is "seventy-three million, two hundred eighteen thousand, five hundred twenty".