805421000 has 32 divisors (see below), whose sum is σ = 1884687480. Its totient is φ = 322168000.

The previous prime is 805420997. The next prime is 805421009. The reversal of 805421000 is 124508.

It can be written as a sum of positive squares in 4 ways, for example, as 137405284 + 668015716 = 11722^2 + 25846^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (805421009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 401711 + ... + 403710.

Almost surely, 2^805421000 is an apocalyptic number.

It is an amenable number.

805421000 is an abundant number, since it is smaller than the sum of its proper divisors (1079266480).

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

805421000 is a wasteful number, since it uses less digits than its factorization.

805421000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 805442 (or 805428 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 805421000 is about 28379.9400985978. The cubic root of 805421000 is about 930.4098859957.

Adding to 805421000 its reverse (124508), we get a palindrome (805545508).

The spelling of 805421000 in words is "eight hundred five million, four hundred twenty-one thousand".