1812821688 has 32 divisors (see below), whose sum is σ = 5035616400. Its totient is φ = 604273824.

The previous prime is 1812821671. The next prime is 1812821701. The reversal of 1812821688 is 8861282181.

1812821688 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4196131 + ... + 4196562.

Almost surely, 2^1812821688 is an apocalyptic number.

1812821688 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1812821688 is an abundant number, since it is smaller than the sum of its proper divisors (3222794712).

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

1812821688 is a wasteful number, since it uses less digits than its factorization.

1812821688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8392708 (or 8392698 counting only the distinct ones).

The product of its digits is 98304, while the sum is 45.

The square root of 1812821688 is about 42577.2437811561. The cubic root of 1812821688 is about 1219.3218680492.

The spelling of 1812821688 in words is "one billion, eight hundred twelve million, eight hundred twenty-one thousand, six hundred eighty-eight".