11506561 has 4 divisors (see below), whose sum is σ = 12552624. Its totient is φ = 10460500.

The previous prime is 11506541. The next prime is 11506567. The reversal of 11506561 is 16560511.

11506561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 11506561 - 2¹⁷ = 11375489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11506567) 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, 523015 + ... + 523036.

It is an arithmetic number, because the mean of its divisors is an integer number (3138156).

Almost surely, 2^11506561 is an apocalyptic number.

11506561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11506561 is a deficient number, since it is larger than the sum of its proper divisors (1046063).

11506561 is a wasteful number, since it uses less digits than its factorization.

11506561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1046062.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 11506561 is about 3392.1322203004. The cubic root of 11506561 is about 225.7607892639.

The spelling of 11506561 in words is "eleven million, five hundred six thousand, five hundred sixty-one".