1979775828 has 72 divisors (see below), whose sum is σ = 5206099080. Its totient is φ = 633588480.

The previous prime is 1979775821. The next prime is 1979775871. The reversal of 1979775828 is 8285779791.

It can be written as a sum of positive squares in 4 ways, for example, as 78641424 + 1901134404 = 8868^2 + 43602^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1979775821) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 183726 + ... + 194202.

Almost surely, 2^1979775828 is an apocalyptic number.

1979775828 is a gapful number since it is divisible by the number (18) 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 1979775828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2603049540).

1979775828 is an abundant number, since it is smaller than the sum of its proper divisors (3226323252).

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

1979775828 is a wasteful number, since it uses less digits than its factorization.

1979775828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10697 (or 10692 counting only the distinct ones).

The product of its digits is 17781120, while the sum is 63.

The square root of 1979775828 is about 44494.6719057462. The cubic root of 1979775828 is about 1255.6598442253.

The spelling of 1979775828 in words is "one billion, nine hundred seventy-nine million, seven hundred seventy-five thousand, eight hundred twenty-eight".