83521440 has 144 divisors (see below), whose sum is σ = 294368256. Its totient is φ = 21542400.

The previous prime is 83521433. The next prime is 83521453. The reversal of 83521440 is 4412538.

It is a tau number, because it is divible by the number of its divisors (144).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43705 + ... + 45575.

It is an arithmetic number, because the mean of its divisors is an integer number (2044224).

Almost surely, 2^83521440 is an apocalyptic number.

83521440 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 83521440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147184128).

83521440 is an abundant number, since it is smaller than the sum of its proper divisors (210846816).

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

83521440 is a wasteful number, since it uses less digits than its factorization.

83521440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1923 (or 1912 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 83521440 is about 9139.0065105568. The cubic root of 83521440 is about 437.1186380094.

Adding to 83521440 its reverse (4412538), we get a palindrome (87933978).

The spelling of 83521440 in words is "eighty-three million, five hundred twenty-one thousand, four hundred forty".