11722021 has 4 divisors (see below), whose sum is σ = 11731392. Its totient is φ = 11712652.

The previous prime is 11722013. The next prime is 11722033. The reversal of 11722021 is 12022711.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12022711 = 967 ⋅12433.

It is a cyclic number.

It is not a de Polignac number, because 11722021 - 2³ = 11722013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11721986 and 11722004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11722001) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 2455 + ... + 5428.

It is an arithmetic number, because the mean of its divisors is an integer number (2932848).

Almost surely, 2^11722021 is an apocalyptic number.

It is an amenable number.

11722021 is a deficient number, since it is larger than the sum of its proper divisors (9371).

11722021 is an equidigital number, since it uses as much as digits as its factorization.

11722021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9370.

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 11722021 is about 3423.7437112027. The cubic root of 11722021 is about 227.1612056543.

Adding to 11722021 its reverse (12022711), we get a palindrome (23744732).

The spelling of 11722021 in words is "eleven million, seven hundred twenty-two thousand, twenty-one".