244000021 has 4 divisors (see below), whose sum is σ = 244040032. Its totient is φ = 243960012.

The previous prime is 244000019. The next prime is 244000037. The reversal of 244000021 is 120000442.

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.

It is a cyclic number.

It is not a de Polignac number, because 244000021 - 2¹ = 244000019 is a prime.

It is the 15621-st Hogben number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 243999965 and 244000010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (244000121) by changing a digit.

It is a nontrivial repunit in base 15620.

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, 8745 + ... + 23758.

It is an arithmetic number, because the mean of its divisors is an integer number (61010008).

Almost surely, 2^244000021 is an apocalyptic number.

It is an amenable number.

244000021 is a deficient number, since it is larger than the sum of its proper divisors (40011).

244000021 is an equidigital number, since it uses as much as digits as its factorization.

244000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40010.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 244000021 is about 15620.5000240069. The cubic root of 244000021 is about 624.8799948795.

Adding to 244000021 its reverse (120000442), we get a palindrome (364000463).

The spelling of 244000021 in words is "two hundred forty-four million, twenty-one", and thus it is an aban number.