1808821400 has 24 divisors (see below), whose sum is σ = 4205510220. Its totient is φ = 723528480.

The previous prime is 1808821393. The next prime is 1808821429. The reversal of 1808821400 is 41288081.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4521854 + ... + 4522253.

Almost surely, 2^1808821400 is an apocalyptic number.

1808821400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1808821400 is an abundant number, since it is smaller than the sum of its proper divisors (2396688820).

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

1808821400 is a wasteful number, since it uses less digits than its factorization.

1808821400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9044123 (or 9044114 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 32.

The square root of 1808821400 is about 42530.2410056656. The cubic root of 1808821400 is about 1218.4243297266.

The spelling of 1808821400 in words is "one billion, eight hundred eight million, eight hundred twenty-one thousand, four hundred".