73000000 has 98 divisors (see below), whose sum is σ = 183552338. Its totient is φ = 28800000.

The previous prime is 72999991. The next prime is 73000003. The reversal of 73000000 is 37.

It can be written as a sum of positive squares in 7 ways, for example, as 72999936 + 64 = 8544^2 + 8^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (73000003) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 999964 + ... + 1000036.

Almost surely, 2^73000000 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 73000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91776169).

73000000 is an abundant number, since it is smaller than the sum of its proper divisors (110552338).

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

73000000 is an frugal number, since it uses more digits than its factorization.

73000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115 (or 80 counting only the distinct ones).

The product of its (nonzero) digits is 21, while the sum is 10.

The square root of 73000000 is about 8544.0037453175. The cubic root of 73000000 is about 417.9339196381.

Adding to 73000000 its reverse (37), we get a palindrome (73000037).

The spelling of 73000000 in words is "seventy-three million", and thus it is an aban number and an uban number.