73640320 has 128 divisors (see below), whose sum is σ = 194322240. Its totient is φ = 26517504.

The previous prime is 73640317. The next prime is 73640321. The reversal of 73640320 is 2304637.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73640321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 440877 + ... + 441043.

Almost surely, 2^73640320 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 73640320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97161120).

73640320 is an abundant number, since it is smaller than the sum of its proper divisors (120681920).

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

73640320 is a wasteful number, since it uses less digits than its factorization.

73640320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 25.

The square root of 73640320 is about 8581.3938261800. The cubic root of 73640320 is about 419.1523341875.

Adding to 73640320 its reverse (2304637), we get a palindrome (75944957).

The spelling of 73640320 in words is "seventy-three million, six hundred forty thousand, three hundred twenty".