11531811 has 4 divisors (see below), whose sum is σ = 15375752. Its totient is φ = 7687872.

The previous prime is 11531801. The next prime is 11531837. The reversal of 11531811 is 11813511.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 11531811 - 2⁷ = 11531683 is a prime.

It is a Duffinian 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 3 ways as a sum of consecutive naturals, for example, 1921966 + ... + 1921971.

It is an arithmetic number, because the mean of its divisors is an integer number (3843938).

Almost surely, 2^11531811 is an apocalyptic number.

11531811 is a deficient number, since it is larger than the sum of its proper divisors (3843941).

11531811 is an equidigital number, since it uses as much as digits as its factorization.

11531811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3843940.

The product of its digits is 120, while the sum is 21.

The square root of 11531811 is about 3395.8520285784. The cubic root of 11531811 is about 225.9258051277.

The spelling of 11531811 in words is "eleven million, five hundred thirty-one thousand, eight hundred eleven".