6621361976544 has 864 divisors, whose sum is σ = 22304937682944. Its totient is φ = 1709248020480.

The previous prime is 6621361976483. The next prime is 6621361976569. The reversal of 6621361976544 is 4456791631266.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 34307574912 + ... + 34307575104.

It is an arithmetic number, because the mean of its divisors is an integer number (25815900096).

Almost surely, 2^{6621361976544} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6621361976544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11152468841472).

6621361976544 is an abundant number, since it is smaller than the sum of its proper divisors (15683575706400).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6621361976544 is a wasteful number, since it uses less digits than its factorization.

6621361976544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520 (or 312 counting only the distinct ones).

The product of its digits is 39191040, while the sum is 60.

The spelling of 6621361976544 in words is "six trillion, six hundred twenty-one billion, three hundred sixty-one million, nine hundred seventy-six thousand, five hundred forty-four".