13155661512 has 144 divisors (see below), whose sum is σ = 41632166160. Its totient is φ = 3741974208.

The previous prime is 13155661501. The next prime is 13155661543. The reversal of 13155661512 is 21516655131.

13155661512 is a `hidden beast` number, since 1 + 31 + 5 + 5 + 6 + 615 + 1 + 2 = 666.

It is a super-2 number, since 2×13155661512² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 792643 + ... + 809069.

It is an arithmetic number, because the mean of its divisors is an integer number (289112265).

Almost surely, 2^13155661512 is an apocalyptic number.

13155661512 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 13155661512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20816083080).

13155661512 is an abundant number, since it is smaller than the sum of its proper divisors (28476504648).

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

13155661512 is a wasteful number, since it uses less digits than its factorization.

13155661512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16680 (or 16666 counting only the distinct ones).

The product of its digits is 27000, while the sum is 36.

The spelling of 13155661512 in words is "thirteen billion, one hundred fifty-five million, six hundred sixty-one thousand, five hundred twelve".