11731821 has 8 divisors (see below), whose sum is σ = 15665760. Its totient is φ = 7809552.

The previous prime is 11731789. The next prime is 11731829. The reversal of 11731821 is 12813711.

It is a happy number.

11731821 is digitally balanced in base 2, because in such base 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 not a de Polignac number, because 11731821 - 2⁵ = 11731789 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11731791 and 11731800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11731829) 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, 211 + ... + 4848.

It is an arithmetic number, because the mean of its divisors is an integer number (1958220).

Almost surely, 2^11731821 is an apocalyptic number.

It is an amenable number.

11731821 is a deficient number, since it is larger than the sum of its proper divisors (3933939).

11731821 is an equidigital number, since it uses as much as digits as its factorization.

11731821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5835.

The product of its digits is 336, while the sum is 24.

The square root of 11731821 is about 3425.1745940901. The cubic root of 11731821 is about 227.2244927990.

The spelling of 11731821 in words is "eleven million, seven hundred thirty-one thousand, eight hundred twenty-one".