11811810 has 16 divisors (see below), whose sum is σ = 28348416. Its totient is φ = 3149808.

The previous prime is 11811797. The next prime is 11811847. The reversal of 11811810 is 1811811.

It is a happy number.

It is a super-2 number, since 2×11811810² = 279037710952200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 196834 + ... + 196893.

It is an arithmetic number, because the mean of its divisors is an integer number (1771776).

Almost surely, 2^11811810 is an apocalyptic number.

11811810 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

11811810 is an abundant number, since it is smaller than the sum of its proper divisors (16536606).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11811810 is a wasteful number, since it uses less digits than its factorization.

11811810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393737.

The product of its (nonzero) digits is 64, while the sum is 21.

The square root of 11811810 is about 3436.8313895215. The cubic root of 11811810 is about 227.7397384204.

Subtracting from 11811810 its reverse (1811811), we obtain a palindrome (9999999).

It can be divided in two parts, 11811 and 810, that added together give a palindrome (12621).

The spelling of 11811810 in words is "eleven million, eight hundred eleven thousand, eight hundred ten".