11820421 has 8 divisors (see below), whose sum is σ = 11987360. Its totient is φ = 11654928.

The previous prime is 11820407. The next prime is 11820433. The reversal of 11820421 is 12402811.

It is a happy number.

11820421 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 a cyclic number.

It is not a de Polignac number, because 11820421 - 2¹⁵ = 11787653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11820481) 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, 38350 + ... + 38656.

It is an arithmetic number, because the mean of its divisors is an integer number (1498420).

Almost surely, 2^11820421 is an apocalyptic number.

It is an amenable number.

11820421 is a deficient number, since it is larger than the sum of its proper divisors (166939).

11820421 is a wasteful number, since it uses less digits than its factorization.

11820421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 723.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 11820421 is about 3438.0839140428. The cubic root of 11820421 is about 227.7950669583.

The spelling of 11820421 in words is "eleven million, eight hundred twenty thousand, four hundred twenty-one".