13661319555072 has 960 divisors, whose sum is σ = 49226675097600. Its totient is φ = 3687451361280.

The previous prime is 13661319555041. The next prime is 13661319555179. The reversal of 13661319555072 is 27055591316631.

It is a happy number.

13661319555072 is a `hidden beast` number, since 1 + 3 + 6 + 6 + 1 + 3 + 19 + 5 + 550 + 72 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

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, 11097740697 + ... + 11097741927.

It is an arithmetic number, because the mean of its divisors is an integer number (51277786560).

Almost surely, 2^{13661319555072} is an apocalyptic number.

13661319555072 is a gapful number since it is divisible by the number (12) 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 13661319555072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24613337548800).

13661319555072 is an abundant number, since it is smaller than the sum of its proper divisors (35565355542528).

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

13661319555072 is a wasteful number, since it uses less digits than its factorization.

13661319555072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1794 (or 1765 counting only the distinct ones).

The product of its (nonzero) digits is 5103000, while the sum is 54.

The spelling of 13661319555072 in words is "thirteen trillion, six hundred sixty-one billion, three hundred nineteen million, five hundred fifty-five thousand, seventy-two".