805005661 has 8 divisors (see below), whose sum is σ = 849454400. Its totient is φ = 760764960.

The previous prime is 805005659. The next prime is 805005671. The reversal of 805005661 is 166500508.

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 805005661 - 2¹ = 805005659 is a prime.

It is a super-2 number, since 2×805005661² = 1296068228484093842, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (805005601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44025 + ... + 59566.

It is an arithmetic number, because the mean of its divisors is an integer number (106181800).

Almost surely, 2^805005661 is an apocalyptic number.

It is an amenable number.

805005661 is a deficient number, since it is larger than the sum of its proper divisors (44448739).

805005661 is a wasteful number, since it uses less digits than its factorization.

805005661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104019.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 805005661 is about 28372.6216800633. The cubic root of 805005661 is about 930.2499274331.

The spelling of 805005661 in words is "eight hundred five million, five thousand, six hundred sixty-one".