11311561 has 8 divisors (see below), whose sum is σ = 11885184. Its totient is φ = 10744800.

The previous prime is 11311541. The next prime is 11311567. The reversal of 11311561 is 16511311.

11311561 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11311561 - 2⁹ = 11311049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11311567) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1845 + ... + 5101.

It is an arithmetic number, because the mean of its divisors is an integer number (1485648).

Almost surely, 2^11311561 is an apocalyptic number.

It is an amenable number.

11311561 is a deficient number, since it is larger than the sum of its proper divisors (573623).

11311561 is a wasteful number, since it uses less digits than its factorization.

11311561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3431.

The product of its digits is 90, while the sum is 19.

The square root of 11311561 is about 3363.2664182309. The cubic root of 11311561 is about 224.4782048375.

Adding to 11311561 its reverse (16511311), we get a palindrome (27822872).

The spelling of 11311561 in words is "eleven million, three hundred eleven thousand, five hundred sixty-one".