551649 has 16 divisors (see below), whose sum is σ = 851840. Its totient is φ = 311040.

The previous prime is 551597. The next prime is 551651. The reversal of 551649 is 946155.

It is not a de Polignac number, because 551649 - 2¹⁹ = 27361 is a prime.

It is a Duffinian number.

Its product of digits (5400) is a multiple of the sum of its prime divisors (360).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 551649.

It is not an unprimeable number, because it can be changed into a prime (551659) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2169 + ... + 2409.

It is an arithmetic number, because the mean of its divisors is an integer number (53240).

2⁵⁵¹⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

551649 is a deficient number, since it is larger than the sum of its proper divisors (300191).

551649 is a wasteful number, since it uses less digits than its factorization.

551649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360.

The product of its digits is 5400, while the sum is 30.

The square root of 551649 is about 742.7307722183. The cubic root of 551649 is about 82.0139278345.

It can be divided in two parts, 5516 and 49, that added together give a triangular number (5565 = T₁₀₅).

The spelling of 551649 in words is "five hundred fifty-one thousand, six hundred forty-nine".