73731220 has 12 divisors (see below), whose sum is σ = 154835604. Its totient is φ = 29492480.

The previous prime is 73731209. The next prime is 73731221. The reversal of 73731220 is 2213737.

It can be written as a sum of positive squares in 2 ways, for example, as 39765636 + 33965584 = 6306^2 + 5828^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73731221) 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, 1843261 + ... + 1843300.

It is an arithmetic number, because the mean of its divisors is an integer number (12902967).

Almost surely, 2^73731220 is an apocalyptic number.

It is an amenable number.

73731220 is an abundant number, since it is smaller than the sum of its proper divisors (81104384).

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

73731220 is a wasteful number, since it uses less digits than its factorization.

73731220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3686570 (or 3686568 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 25.

The square root of 73731220 is about 8586.6885351688. The cubic root of 73731220 is about 419.3247274314.

Adding to 73731220 its reverse (2213737), we get a palindrome (75944957).

The spelling of 73731220 in words is "seventy-three million, seven hundred thirty-one thousand, two hundred twenty".