805981621 has 8 divisors (see below), whose sum is σ = 817257600. Its totient is φ = 794732640.

The previous prime is 805981613. The next prime is 805981667. The reversal of 805981621 is 126189508.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 805981621 - 2³ = 805981613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (805981681) 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, 57606 + ... + 70216.

It is an arithmetic number, because the mean of its divisors is an integer number (102157200).

Almost surely, 2^805981621 is an apocalyptic number.

It is an amenable number.

805981621 is a deficient number, since it is larger than the sum of its proper divisors (11275979).

805981621 is a wasteful number, since it uses less digits than its factorization.

805981621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13499.

The product of its (nonzero) digits is 34560, while the sum is 40.

The square root of 805981621 is about 28389.8154449796. The cubic root of 805981621 is about 930.6257094984.

The spelling of 805981621 in words is "eight hundred five million, nine hundred eighty-one thousand, six hundred twenty-one".