6444345031221 has 4 divisors (see below), whose sum is σ = 8592460041632. Its totient is φ = 4296230020812.

The previous prime is 6444345031219. The next prime is 6444345031231. The reversal of 6444345031221 is 1221305434446.

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 not a de Polignac number, because 6444345031221 - 2¹ = 6444345031219 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6444345031221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6444345031231) 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, 1074057505201 + ... + 1074057505206.

It is an arithmetic number, because the mean of its divisors is an integer number (2148115010408).

Almost surely, 2^{6444345031221} is an apocalyptic number.

It is an amenable number.

6444345031221 is a deficient number, since it is larger than the sum of its proper divisors (2148115010411).

6444345031221 is a wasteful number, since it uses less digits than its factorization.

6444345031221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2148115010410.

The product of its (nonzero) digits is 276480, while the sum is 39.

The spelling of 6444345031221 in words is "six trillion, four hundred forty-four billion, three hundred forty-five million, thirty-one thousand, two hundred twenty-one".