551631 has 4 divisors (see below), whose sum is σ = 735512. Its totient is φ = 367752.

The previous prime is 551597. The next prime is 551651. The reversal of 551631 is 136155.

It is a happy number.

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

It is not a de Polignac number, because 551631 - 2⁷ = 551503 is a prime.

It is a super-2 number, since 2×551631² = 608593520322, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 551598 and 551607.

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 551631.

It is not an unprimeable number, because it can be changed into a prime (551651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91936 + ... + 91941.

It is an arithmetic number, because the mean of its divisors is an integer number (183878).

2⁵⁵¹⁶³¹ is an apocalyptic number.

551631 is a deficient number, since it is larger than the sum of its proper divisors (183881).

551631 is a wasteful number, since it uses less digits than its factorization.

551631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183880.

The product of its digits is 450, while the sum is 21.

The square root of 551631 is about 742.7186546735. The cubic root of 551631 is about 82.0130358018.

Adding to 551631 its reverse (136155), we get a palindrome (687786).

The spelling of 551631 in words is "five hundred fifty-one thousand, six hundred thirty-one".