2638660976640 has 1200 divisors, whose sum is σ = 10304374800720. Its totient is φ = 645928058880.

The previous prime is 2638660976603. The next prime is 2638660976669. The reversal of 2638660976640 is 466790668362.

It can be written as a sum of positive squares in 8 ways, for example, as 2553041534976 + 85619441664 = 1597824^2 + 292608^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 14578237350 + ... + 14578237530.

Almost surely, 2^{2638660976640} is an apocalyptic number.

2638660976640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2638660976640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5152187400360).

2638660976640 is an abundant number, since it is smaller than the sum of its proper divisors (7665713824080).

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

2638660976640 is an frugal number, since it uses more digits than its factorization.

2638660976640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 94058496, while the sum is 63.

The spelling of 2638660976640 in words is "two trillion, six hundred thirty-eight billion, six hundred sixty million, nine hundred seventy-six thousand, six hundred forty".