511649 has 4 divisors (see below), whose sum is σ = 541764. Its totient is φ = 481536.

The previous prime is 511633. The next prime is 511669. The reversal of 511649 is 946115.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 946115 = 5 ⋅189223.

It can be written as a sum of positive squares in 2 ways, for example, as 160000 + 351649 = 400^2 + 593^2 .

It is a cyclic number.

It is not a de Polignac number, because 511649 - 2⁴ = 511633 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (511669) 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, 15032 + ... + 15065.

It is an arithmetic number, because the mean of its divisors is an integer number (135441).

2⁵¹¹⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

511649 is a deficient number, since it is larger than the sum of its proper divisors (30115).

511649 is a wasteful number, since it uses less digits than its factorization.

511649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30114.

The product of its digits is 1080, while the sum is 26.

The square root of 511649 is about 715.2964420434. The cubic root of 511649 is about 79.9817145709.

The spelling of 511649 in words is "five hundred eleven thousand, six hundred forty-nine".