551565 has 48 divisors (see below), whose sum is σ = 1168128. Its totient is φ = 235008.

The previous prime is 551557. The next prime is 551569. The reversal of 551565 is 565155.

It is not a de Polignac number, because 551565 - 2³ = 551557 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

551565 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551569) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5304 + ... + 5406.

It is an arithmetic number, because the mean of its divisors is an integer number (24336).

2⁵⁵¹⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

551565 is an abundant number, since it is smaller than the sum of its proper divisors (616563).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

551565 is a wasteful number, since it uses less digits than its factorization.

551565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 135 counting only the distinct ones).

The product of its digits is 3750, while the sum is 27.

The square root of 551565 is about 742.6742219843. The cubic root of 551565 is about 82.0097648494.

The spelling of 551565 in words is "five hundred fifty-one thousand, five hundred sixty-five".