83312640 has 180 divisors, whose sum is σ = 291364164. Its totient is φ = 22020096.

The previous prime is 83312639. The next prime is 83312651. The reversal of 83312640 is 4621338.

It is a happy number.

83312640 is a `hidden beast` number, since 8 + 3 + 3 + 12 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 11943936 + 71368704 = 3456^2 + 8448^2 .

It is a tau number, because it is divible by the number of its divisors (180).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 737224 + ... + 737336.

Almost surely, 2^83312640 is an apocalyptic number.

83312640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 83312640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145682082).

83312640 is an abundant number, since it is smaller than the sum of its proper divisors (208051524).

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

83312640 is a wasteful number, since it uses less digits than its factorization.

83312640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 83312640 is about 9127.5758008356. The cubic root of 83312640 is about 436.7540747916.

Adding to 83312640 its reverse (4621338), we get a palindrome (87933978).

The spelling of 83312640 in words is "eighty-three million, three hundred twelve thousand, six hundred forty".