1809971828 has 24 divisors (see below), whose sum is σ = 3736717824. Its totient is φ = 750679200.

The previous prime is 1809971777. The next prime is 1809971881. The reversal of 1809971828 is 8281799081.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1809971828.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1041743 + ... + 1043478.

It is an arithmetic number, because the mean of its divisors is an integer number (155696576).

Almost surely, 2^1809971828 is an apocalyptic number.

It is an amenable number.

1809971828 is an abundant number, since it is smaller than the sum of its proper divisors (1926745996).

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

1809971828 is a wasteful number, since it uses less digits than its factorization.

1809971828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2085263 (or 2085261 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 53.

The square root of 1809971828 is about 42543.7636792985. The cubic root of 1809971828 is about 1218.6825848908.

The spelling of 1809971828 in words is "one billion, eight hundred nine million, nine hundred seventy-one thousand, eight hundred twenty-eight".