80905680 has 120 divisors (see below), whose sum is σ = 279143592. Its totient is φ = 20984832.

The previous prime is 80905637. The next prime is 80905687. The reversal of 80905680 is 8650908.

80905680 is a `hidden beast` number, since 8 + 0 + 90 + 568 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 36869184 + 44036496 = 6072^2 + 6636^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80905687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25122 + ... + 28158.

Almost surely, 2^80905680 is an apocalyptic number.

80905680 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 80905680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139571796).

80905680 is an abundant number, since it is smaller than the sum of its proper divisors (198237912).

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

80905680 is a wasteful number, since it uses less digits than its factorization.

80905680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3093 (or 3084 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 80905680 is about 8994.7584736890. The cubic root of 80905680 is about 432.5068639137.

The spelling of 80905680 in words is "eighty million, nine hundred five thousand, six hundred eighty".