531649 has 4 divisors (see below), whose sum is σ = 540720. Its totient is φ = 522580.

The previous prime is 531637. The next prime is 531667. The reversal of 531649 is 946135.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 531649 - 2⁷ = 531521 is a prime.

It is a Duffinian number.

531649 is a lucky number.

It is a plaindrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (531689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4447 + ... + 4564.

It is an arithmetic number, because the mean of its divisors is an integer number (135180).

531649 is a Friedman number, since it can be written as 9^6+41*5+3, using all its digits and the basic arithmetic operations.

2⁵³¹⁶⁴⁹ is an apocalyptic number.

531649 is a gapful number since it is divisible by the number (59) formed by its first and last digit.

It is an amenable number.

531649 is a deficient number, since it is larger than the sum of its proper divisors (9071).

531649 is an equidigital number, since it uses as much as digits as its factorization.

531649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9070.

The product of its digits is 3240, while the sum is 28.

The square root of 531649 is about 729.1426472234. The cubic root of 531649 is about 81.0105661164.

The spelling of 531649 in words is "five hundred thirty-one thousand, six hundred forty-nine".