820135044 has 135 divisors (see below), whose sum is σ = 2255942997. Its totient is φ = 259803936.

The previous prime is 820135037. The next prime is 820135079. The reversal of 820135044 is 440531028.

The square root of 820135044 is 28638.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 733868100 + 86266944 = 27090^2 + 9288^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 820134999 and 820135017.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 19072887 + ... + 19072929.

Almost surely, 2^820135044 is an apocalyptic number.

820135044 is the 28638-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 820135044

820135044 is an abundant number, since it is smaller than the sum of its proper divisors (1435807953).

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

820135044 is a wasteful number, since it uses less digits than its factorization.

820135044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176 (or 85 counting only the distinct ones).

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

The cubic root of 820135044 is about 936.0415415488.

The spelling of 820135044 in words is "eight hundred twenty million, one hundred thirty-five thousand, forty-four".