22163821 has 8 divisors (see below), whose sum is σ = 22942584. Its totient is φ = 21396480.

The previous prime is 22163807. The next prime is 22163833. The reversal of 22163821 is 12836122.

It can be written as a sum of positive squares in 4 ways, for example, as 902500 + 21261321 = 950^2 + 4611^2 .

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 22163821 - 2⁷ = 22163693 is a prime.

It is a super-2 number, since 2×22163821² = 982469922640082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22163891) 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, 1191 + ... + 6763.

It is an arithmetic number, because the mean of its divisors is an integer number (2867823).

Almost surely, 2^22163821 is an apocalyptic number.

It is an amenable number.

22163821 is a deficient number, since it is larger than the sum of its proper divisors (778763).

22163821 is an equidigital number, since it uses as much as digits as its factorization.

22163821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5711.

The product of its digits is 1152, while the sum is 25.

The square root of 22163821 is about 4707.8467477181. The cubic root of 22163821 is about 280.8977182068.

Adding to 22163821 its reverse (12836122), we get a palindrome (34999943).

The spelling of 22163821 in words is "twenty-two million, one hundred sixty-three thousand, eight hundred twenty-one".