805221900 has 486 divisors, whose sum is σ = 3193428420. Its totient is φ = 168739200.

The previous prime is 805221889. The next prime is 805221943. The reversal of 805221900 is 9122508.

It is a super-2 number, since 2×805221900² = 1296764616479220000, which contains 22 as substring.

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 161 ways as a sum of consecutive naturals, for example, 25974885 + ... + 25974915.

Almost surely, 2^805221900 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 805221900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1596714210).

805221900 is an abundant number, since it is smaller than the sum of its proper divisors (2388206520).

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

805221900 is a wasteful number, since it uses less digits than its factorization.

805221900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115 (or 67 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 805221900 is about 28376.4321224498. The cubic root of 805221900 is about 930.3332139303. Note that the first 3 decimals are identical.

The spelling of 805221900 in words is "eight hundred five million, two hundred twenty-one thousand, nine hundred".