73081638 has 120 divisors (see below), whose sum is σ = 196630200. Its totient is φ = 19559232.

The previous prime is 73081633. The next prime is 73081667. The reversal of 73081638 is 83618037.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73081633) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 821098 + ... + 821186.

It is an arithmetic number, because the mean of its divisors is an integer number (1638585).

Almost surely, 2^73081638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 73081638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98315100).

73081638 is an abundant number, since it is smaller than the sum of its proper divisors (123548562).

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

73081638 is a wasteful number, since it uses less digits than its factorization.

73081638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 73081638 is about 8548.7799129466. The cubic root of 73081638 is about 418.0896574389.

The spelling of 73081638 in words is "seventy-three million, eighty-one thousand, six hundred thirty-eight".