3657217978128 has 960 divisors, whose sum is σ = 11937315962880. Its totient is φ = 956938752000.

The previous prime is 3657217978121. The next prime is 3657217978147. The reversal of 3657217978128 is 8218797127563.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is not an unprimeable number, because it can be changed into a prime (3657217978121) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 9804873750 + ... + 9804874122.

It is an arithmetic number, because the mean of its divisors is an integer number (12434704128).

Almost surely, 2^{3657217978128} 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 3657217978128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5968657981440).

3657217978128 is an abundant number, since it is smaller than the sum of its proper divisors (8280097984752).

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

3657217978128 is a wasteful number, since it uses less digits than its factorization.

3657217978128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580 (or 563 counting only the distinct ones).

The product of its digits is 71124480, while the sum is 66.

The spelling of 3657217978128 in words is "three trillion, six hundred fifty-seven billion, two hundred seventeen million, nine hundred seventy-eight thousand, one hundred twenty-eight".