80820644 has 12 divisors (see below), whose sum is σ = 141503964. Its totient is φ = 40390944.

The previous prime is 80820637. The next prime is 80820647. The reversal of 80820644 is 44602808.

It can be written as a sum of positive squares in 2 ways, for example, as 30580900 + 50239744 = 5530^2 + 7088^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 80820644.

It is not an unprimeable number, because it can be changed into a prime (80820647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8822 + ... + 15474.

It is an arithmetic number, because the mean of its divisors is an integer number (11791997).

Almost surely, 2^80820644 is an apocalyptic number.

It is an amenable number.

80820644 is a deficient number, since it is larger than the sum of its proper divisors (60683320).

80820644 is a wasteful number, since it uses less digits than its factorization.

80820644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9694 (or 9692 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 32.

The square root of 80820644 is about 8990.0302557889. The cubic root of 80820644 is about 432.3552818632.

The spelling of 80820644 in words is "eighty million, eight hundred twenty thousand, six hundred forty-four".