551663 has 4 divisors (see below), whose sum is σ = 630480. Its totient is φ = 472848.

The previous prime is 551659. The next prime is 551671. The reversal of 551663 is 366155.

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 551663 - 2² = 551659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 551663.

It is not an unprimeable number, because it can be changed into a prime (551653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39398 + ... + 39411.

It is an arithmetic number, because the mean of its divisors is an integer number (157620).

2⁵⁵¹⁶⁶³ is an apocalyptic number.

551663 is a deficient number, since it is larger than the sum of its proper divisors (78817).

551663 is an equidigital number, since it uses as much as digits as its factorization.

551663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78816.

The product of its digits is 2700, while the sum is 26.

The square root of 551663 is about 742.7401968387. The cubic root of 551663 is about 82.0146216242.

The spelling of 551663 in words is "five hundred fifty-one thousand, six hundred sixty-three".