820064880 has 60 divisors (see below), whose sum is σ = 2754053640. Its totient is φ = 218683776.

The previous prime is 820064873. The next prime is 820064897. The reversal of 820064880 is 88460028.

820064880 is a `hidden beast` number, since 8 + 2 + 0 + 0 + 648 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

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

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, 568770 + ... + 570209.

It is an arithmetic number, because the mean of its divisors is an integer number (45900894).

Almost surely, 2^820064880 is an apocalyptic number.

820064880 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

820064880 is an abundant number, since it is smaller than the sum of its proper divisors (1933988760).

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

820064880 is a wasteful number, since it uses less digits than its factorization.

820064880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1138998 (or 1138989 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 36.

The square root of 820064880 is about 28636.7749580849. The cubic root of 820064880 is about 936.0148474524.

The spelling of 820064880 in words is "eight hundred twenty million, sixty-four thousand, eight hundred eighty".