111661167798180 has 4320 divisors, whose sum is σ = 503471024179200. Its totient is φ = 20661255014400.

The previous prime is 111661167798143. The next prime is 111661167798269. The reversal of 111661167798180 is 81897761166111.

111661167798180 is a `hidden beast` number, since 1 + 1 + 1 + 6 + 611 + 6 + 7 + 7 + 9 + 8 + 1 + 8 + 0 = 666.

It is a super-2 number, since 2×111661167798180² (a number of 29 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 1439 ways as a sum of consecutive naturals, for example, 352243431382 + ... + 352243431698.

It is an arithmetic number, because the mean of its divisors is an integer number (116544218560).

Almost surely, 2^{111661167798180} is an apocalyptic number.

111661167798180 is a gapful number since it is divisible by the number (10) 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 111661167798180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (251735512089600).

111661167798180 is an abundant number, since it is smaller than the sum of its proper divisors (391809856381020).

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

111661167798180 is a wasteful number, since it uses less digits than its factorization.

111661167798180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438 (or 389 counting only the distinct ones).

The product of its (nonzero) digits is 6096384, while the sum is 63.

The spelling of 111661167798180 in words is "one hundred eleven trillion, six hundred sixty-one billion, one hundred sixty-seven million, seven hundred ninety-eight thousand, one hundred eighty".