6921229981647 has 16 divisors (see below), whose sum is σ = 9771201752832. Its totient is φ = 4342708740480.

The previous prime is 6921229981619. The next prime is 6921229981651. The reversal of 6921229981647 is 7461899221296.

It is not a de Polignac number, because 6921229981647 - 2²⁴ = 6921213204431 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6921229982647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16178572 + ... + 16600862.

It is an arithmetic number, because the mean of its divisors is an integer number (610700109552).

Almost surely, 2^{6921229981647} is an apocalyptic number.

6921229981647 is a deficient number, since it is larger than the sum of its proper divisors (2849971771185).

6921229981647 is a wasteful number, since it uses less digits than its factorization.

6921229981647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 743678.

The product of its digits is 47029248, while the sum is 66.

The spelling of 6921229981647 in words is "six trillion, nine hundred twenty-one billion, two hundred twenty-nine million, nine hundred eighty-one thousand, six hundred forty-seven".