11858561 has 12 divisors (see below), whose sum is σ = 14010480. Its totient is φ = 9949680.

The previous prime is 11858557. The next prime is 11858569. The reversal of 11858561 is 16585811.

It is not a de Polignac number, because 11858561 - 2² = 11858557 is a prime.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (11858569) 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 11 ways as a sum of consecutive naturals, for example, 1331 + ... + 5048.

It is an arithmetic number, because the mean of its divisors is an integer number (1167540).

Almost surely, 2^11858561 is an apocalyptic number.

11858561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11858561 is a deficient number, since it is larger than the sum of its proper divisors (2151919).

11858561 is a wasteful number, since it uses less digits than its factorization.

11858561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6416 (or 6403 counting only the distinct ones).

The product of its digits is 9600, while the sum is 35.

The square root of 11858561 is about 3443.6261411483. The cubic root of 11858561 is about 228.0398065821.

The spelling of 11858561 in words is "eleven million, eight hundred fifty-eight thousand, five hundred sixty-one".