905561 has 4 divisors (see below), whose sum is σ = 910800. Its totient is φ = 900324.

The previous prime is 905551. The next prime is 905581. The reversal of 905561 is 165509.

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 905561 - 2⁶ = 905497 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 905561.

It is not an unprimeable number, because it can be changed into a prime (905551) 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, 2351 + ... + 2708.

It is an arithmetic number, because the mean of its divisors is an integer number (227700).

2⁹⁰⁵⁵⁶¹ is an apocalyptic number.

It is an amenable number.

905561 is a deficient number, since it is larger than the sum of its proper divisors (5239).

905561 is a wasteful number, since it uses less digits than its factorization.

905561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5238.

The product of its (nonzero) digits is 1350, while the sum is 26.

The square root of 905561 is about 951.6096888956. The cubic root of 905561 is about 96.7473853473.

It can be divided in two parts, 905 and 561, that multiplied together give a palindrome (507705).

The spelling of 905561 in words is "nine hundred five thousand, five hundred sixty-one".