11621821 has 4 divisors (see below), whose sum is σ = 11630944. Its totient is φ = 11612700.

The previous prime is 11621809. The next prime is 11621839. The reversal of 11621821 is 12812611.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 11621821 - 2¹³ = 11613629 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11621792 and 11621801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11621801) 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, 2265 + ... + 5326.

It is an arithmetic number, because the mean of its divisors is an integer number (2907736).

Almost surely, 2^11621821 is an apocalyptic number.

It is an amenable number.

11621821 is a deficient number, since it is larger than the sum of its proper divisors (9123).

11621821 is an equidigital number, since it uses as much as digits as its factorization.

11621821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9122.

The product of its digits is 192, while the sum is 22.

The square root of 11621821 is about 3409.0792011920. The cubic root of 11621821 is about 226.5120935282.

The spelling of 11621821 in words is "eleven million, six hundred twenty-one thousand, eight hundred twenty-one".