863921005 has 4 divisors (see below), whose sum is σ = 1036705212. Its totient is φ = 691136800.

The previous prime is 863920997. The next prime is 863921017. The reversal of 863921005 is 500129368.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 558755044 + 305165961 = 23638^2 + 17469^2 .

It is not a de Polignac number, because 863921005 - 2³ = 863920997 is a prime.

It is a Duffinian number.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 86392096 + ... + 86392105.

It is an arithmetic number, because the mean of its divisors is an integer number (259176303).

Almost surely, 2^863921005 is an apocalyptic number.

It is an amenable number.

863921005 is a deficient number, since it is larger than the sum of its proper divisors (172784207).

863921005 is a wasteful number, since it uses less digits than its factorization.

863921005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172784206.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 863921005 is about 29392.5331504449. The cubic root of 863921005 is about 952.4116032717.

The spelling of 863921005 in words is "eight hundred sixty-three million, nine hundred twenty-one thousand, five".