1811209028 has 6 divisors (see below), whose sum is σ = 3169615806. Its totient is φ = 905604512.

The previous prime is 1811209003. The next prime is 1811209039. The reversal of 1811209028 is 8209021181.

It can be written as a sum of positive squares in only one way, i.e., 1677066304 + 134142724 = 40952^2 + 11582^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1811208985 and 1811209003.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 226401125 + ... + 226401132.

It is an arithmetic number, because the mean of its divisors is an integer number (528269301).

Almost surely, 2^1811209028 is an apocalyptic number.

It is an amenable number.

1811209028 is a deficient number, since it is larger than the sum of its proper divisors (1358406778).

1811209028 is a wasteful number, since it uses less digits than its factorization.

1811209028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452802261 (or 452802259 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 32.

The square root of 1811209028 is about 42558.3015168604. The cubic root of 1811209028 is about 1218.9601970726.

The spelling of 1811209028 in words is "one billion, eight hundred eleven million, two hundred nine thousand, twenty-eight".