5509781 has 4 divisors (see below), whose sum is σ = 5658732. Its totient is φ = 5360832.

The previous prime is 5509769. The next prime is 5509783. The reversal of 5509781 is 1879055.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3363556 + 2146225 = 1834^2 + 1465^2 .

It is a cyclic number.

It is not a de Polignac number, because 5509781 - 2¹⁰ = 5508757 is a prime.

It is a super-2 number, since 2×5509781² = 60715373335922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5509783) 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, 74420 + ... + 74493.

It is an arithmetic number, because the mean of its divisors is an integer number (1414683).

Almost surely, 2^5509781 is an apocalyptic number.

It is an amenable number.

5509781 is a deficient number, since it is larger than the sum of its proper divisors (148951).

5509781 is a wasteful number, since it uses less digits than its factorization.

5509781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148950.

The product of its (nonzero) digits is 12600, while the sum is 35.

The square root of 5509781 is about 2347.2922698292. The cubic root of 5509781 is about 176.6219921848.

The spelling of 5509781 in words is "five million, five hundred nine thousand, seven hundred eighty-one".