73737728 has 40 divisors (see below), whose sum is σ = 149889960. Its totient is φ = 36229120.

The previous prime is 73737709. The next prime is 73737791. The reversal of 73737728 is 82773737.

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 3 ways as a sum of consecutive naturals, for example, 28988 + ... + 31428.

It is an arithmetic number, because the mean of its divisors is an integer number (3747249).

Almost surely, 2^73737728 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 73737728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (74944980).

73737728 is an abundant number, since it is smaller than the sum of its proper divisors (76152232).

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

73737728 is an equidigital number, since it uses as much as digits as its factorization.

73737728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2518 (or 2502 counting only the distinct ones).

The product of its digits is 345744, while the sum is 44.

The square root of 73737728 is about 8587.0674854691. The cubic root of 73737728 is about 419.3370645166.

The spelling of 73737728 in words is "seventy-three million, seven hundred thirty-seven thousand, seven hundred twenty-eight".