21444285949 has 4 divisors (see below), whose sum is σ = 21462262236. Its totient is φ = 21426309664.

The previous prime is 21444285943. The next prime is 21444285959. The reversal of 21444285949 is 94958244412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5923611225 + 15520674724 = 76965^2 + 124582^2 .

It is a cyclic number.

It is not a de Polignac number, because 21444285949 - 2⁵ = 21444285917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21444285896 and 21444285905.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21444285943) 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, 8986354 + ... + 8988739.

It is an arithmetic number, because the mean of its divisors is an integer number (5365565559).

Almost surely, 2^21444285949 is an apocalyptic number.

It is an amenable number.

21444285949 is a deficient number, since it is larger than the sum of its proper divisors (17976287).

21444285949 is a wasteful number, since it uses less digits than its factorization.

21444285949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17976286.

The product of its digits is 3317760, while the sum is 52.

The spelling of 21444285949 in words is "twenty-one billion, four hundred forty-four million, two hundred eighty-five thousand, nine hundred forty-nine".