11531861 has 8 divisors (see below), whose sum is σ = 12604800. Its totient is φ = 10463040.

The previous prime is 11531843. The next prime is 11531881. The reversal of 11531861 is 16813511.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11531861 is a prime.

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 11531861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11531801) 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, 10580 + ... + 11618.

It is an arithmetic number, because the mean of its divisors is an integer number (1575600).

Almost surely, 2^11531861 is an apocalyptic number.

11531861 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11531861 is a deficient number, since it is larger than the sum of its proper divisors (1072939).

11531861 is a wasteful number, since it uses less digits than its factorization.

11531861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2059.

The product of its digits is 720, while the sum is 26.

The square root of 11531861 is about 3395.8593904931. The cubic root of 11531861 is about 225.9261316527.

The spelling of 11531861 in words is "eleven million, five hundred thirty-one thousand, eight hundred sixty-one".