805220870281 has 9 divisors (see below), whose sum is σ = 807958941069. Its totient is φ = 802492056300.

The previous prime is 805220870243. The next prime is 805220870287. The reversal of 805220870281 is 182078022508.

The square root of 805220870281 is 897341.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 805220870281 - 2³⁹ = 255465056393 is a prime.

It is a super-2 number, since 2×805220870281² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (805220870287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 297018516 + ... + 297021226.

Almost surely, 2^805220870281 is an apocalyptic number.

805220870281 is the 897341-st square number.

805220870281 is the 448671-st centered octagonal number.

It is an amenable number.

805220870281 is a deficient number, since it is larger than the sum of its proper divisors (2738070788).

805220870281 is an frugal number, since it uses more digits than its factorization.

805220870281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6084 (or 3042 counting only the distinct ones).

The product of its (nonzero) digits is 143360, while the sum is 43.

Adding to 805220870281 its reverse (182078022508), we get a palindrome (987298892789).

The spelling of 805220870281 in words is "eight hundred five billion, two hundred twenty million, eight hundred seventy thousand, two hundred eighty-one".