18611978112 has 432 divisors, whose sum is σ = 67497749280. Its totient is φ = 4906137600.

The previous prime is 18611978107. The next prime is 18611978117. The reversal of 18611978112 is 21187911681.

18611978112 is a `hidden beast` number, since 18 + 611 + 9 + 7 + 8 + 1 + 12 = 666.

It is an interprime number because it is at equal distance from previous prime (18611978107) and next prime (18611978117).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18611978117) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 9538737 + ... + 9540687.

It is an arithmetic number, because the mean of its divisors is an integer number (156244790).

Almost surely, 2^18611978112 is an apocalyptic number.

18611978112 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 18611978112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33748874640).

18611978112 is an abundant number, since it is smaller than the sum of its proper divisors (48885771168).

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

18611978112 is a wasteful number, since it uses less digits than its factorization.

18611978112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2011 (or 1976 counting only the distinct ones).

The product of its digits is 48384, while the sum is 45.

The spelling of 18611978112 in words is "eighteen billion, six hundred eleven million, nine hundred seventy-eight thousand, one hundred twelve".