2556561651600 has 480 divisors, whose sum is σ = 9497437839360. Its totient is φ = 581333760000.

The previous prime is 2556561651593. The next prime is 2556561651613. The reversal of 2556561651600 is 61561656552.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 2556561651600.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 25280337 + ... + 25381263.

It is an arithmetic number, because the mean of its divisors is an integer number (19786328832).

Almost surely, 2^{2556561651600} is an apocalyptic number.

2556561651600 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 2556561651600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4748718919680).

2556561651600 is an abundant number, since it is smaller than the sum of its proper divisors (6940876187760).

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

2556561651600 is a wasteful number, since it uses less digits than its factorization.

2556561651600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101079 (or 101068 counting only the distinct ones).

The product of its (nonzero) digits is 1620000, while the sum is 48.

The spelling of 2556561651600 in words is "two trillion, five hundred fifty-six billion, five hundred sixty-one million, six hundred fifty-one thousand, six hundred".