820445280 has 48 divisors (see below), whose sum is σ = 2584404144. Its totient is φ = 218785280.

The previous prime is 820445243. The next prime is 820445389. The reversal of 820445280 is 82544028.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (48).

It is a zygodrome in base 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 854151 + ... + 855110.

It is an arithmetic number, because the mean of its divisors is an integer number (53841753).

Almost surely, 2^820445280 is an apocalyptic number.

820445280 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

820445280 is an abundant number, since it is smaller than the sum of its proper divisors (1763958864).

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

820445280 is a wasteful number, since it uses less digits than its factorization.

820445280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1709279 (or 1709271 counting only the distinct ones).

The product of its (nonzero) digits is 20480, while the sum is 33.

The square root of 820445280 is about 28643.4159973981. The cubic root of 820445280 is about 936.1595534857.

The spelling of 820445280 in words is "eight hundred twenty million, four hundred forty-five thousand, two hundred eighty".