551531 has 4 divisors (see below), whose sum is σ = 583992. Its totient is φ = 519072.

The previous prime is 551519. The next prime is 551539. The reversal of 551531 is 135155.

It is a happy number.

551531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 135155 = 5 ⋅27031.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-551531 is a prime.

It is a super-2 number, since 2×551531² = 608372887922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (551539) 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, 16205 + ... + 16238.

It is an arithmetic number, because the mean of its divisors is an integer number (145998).

2⁵⁵¹⁵³¹ is an apocalyptic number.

551531 is a deficient number, since it is larger than the sum of its proper divisors (32461).

551531 is a wasteful number, since it uses less digits than its factorization.

551531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32460.

The product of its digits is 375, while the sum is 20.

The square root of 551531 is about 742.6513313797. The cubic root of 551531 is about 82.0080797115.

Adding to 551531 its reverse (135155), we get a palindrome (686686).

The spelling of 551531 in words is "five hundred fifty-one thousand, five hundred thirty-one".