2661544974816 has 1440 divisors, whose sum is σ = 10605614009760. Its totient is φ = 646746218496.

The previous prime is 2661544974769. The next prime is 2661544974899. The reversal of 2661544974816 is 6184794451662.

2661544974816 is a `hidden beast` number, since 2 + 6 + 6 + 1 + 544 + 9 + 7 + 4 + 81 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 1160724966 + ... + 1160727258.

It is an arithmetic number, because the mean of its divisors is an integer number (7365009729).

Almost surely, 2^{2661544974816} is an apocalyptic number.

2661544974816 is a gapful number since it is divisible by the number (26) 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 2661544974816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5302807004880).

2661544974816 is an abundant number, since it is smaller than the sum of its proper divisors (7944069034944).

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

2661544974816 is a wasteful number, since it uses less digits than its factorization.

2661544974816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2398 (or 2374 counting only the distinct ones).

The product of its digits is 69672960, while the sum is 63.

The spelling of 2661544974816 in words is "two trillion, six hundred sixty-one billion, five hundred forty-four million, nine hundred seventy-four thousand, eight hundred sixteen".