551881 has 6 divisors (see below), whose sum is σ = 606746. Its totient is φ = 501600.

The previous prime is 551861. The next prime is 551909. The reversal of 551881 is 188155.

551881 is nontrivially palindromic in base 3.

551881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 435600 + 116281 = 660^2 + 341^2 .

It is not a de Polignac number, because 551881 - 2⁵ = 551849 is a prime.

It is a super-2 number, since 2×551881² = 609145276322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (551801) by changing a digit.

It is a nontrivial repunit in base 27.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2160 + ... + 2401.

2⁵⁵¹⁸⁸¹ is an apocalyptic number.

It is an amenable number.

551881 is a deficient number, since it is larger than the sum of its proper divisors (54865).

551881 is a wasteful number, since it uses less digits than its factorization.

551881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4583 (or 4572 counting only the distinct ones).

The product of its digits is 1600, while the sum is 28.

The square root of 551881 is about 742.8869362157. The cubic root of 551881 is about 82.0254234078.

It can be divided in two parts, 55 and 1881, that added together give a square (1936 = 44²).

The spelling of 551881 in words is "five hundred fifty-one thousand, eight hundred eighty-one".