1811491128 has 48 divisors (see below), whose sum is σ = 5087835480. Its totient is φ = 603829728.

The previous prime is 1811491091. The next prime is 1811491133. The reversal of 1811491128 is 8211941181.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 1811491092 and 1811491101.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 463975 + ... + 467862.

Almost surely, 2^1811491128 is an apocalyptic number.

1811491128 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1811491128 is an abundant number, since it is smaller than the sum of its proper divisors (3276344352).

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

1811491128 is an equidigital number, since it uses as much as digits as its factorization.

1811491128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 931858 (or 931842 counting only the distinct ones).

The product of its digits is 4608, while the sum is 36.

The square root of 1811491128 is about 42561.6156648217. The cubic root of 1811491128 is about 1219.0234790783.

The spelling of 1811491128 in words is "one billion, eight hundred eleven million, four hundred ninety-one thousand, one hundred twenty-eight".