551805871 has 4 divisors (see below), whose sum is σ = 552786552. Its totient is φ = 550825192.

The previous prime is 551805869. The next prime is 551805889. The reversal of 551805871 is 178508155.

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

It is a cyclic number.

It is not a de Polignac number, because 551805871 - 2¹ = 551805869 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551805571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 489496 + ... + 490621.

It is an arithmetic number, because the mean of its divisors is an integer number (138196638).

Almost surely, 2^551805871 is an apocalyptic number.

551805871 is a deficient number, since it is larger than the sum of its proper divisors (980681).

551805871 is an equidigital number, since it uses as much as digits as its factorization.

551805871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 980680.

The product of its (nonzero) digits is 56000, while the sum is 40.

The square root of 551805871 is about 23490.5485461706. The cubic root of 551805871 is about 820.2170112725.

The spelling of 551805871 in words is "five hundred fifty-one million, eight hundred five thousand, eight hundred seventy-one".