381981638178036 has 168 divisors, whose sum is σ = 1079503670634984. Its totient is φ = 117514875582720.

The previous prime is 381981638177999. The next prime is 381981638178037. The reversal of 381981638178036 is 630871836189183.

381981638178036 is a `hidden beast` number, since 3 + 81 + 98 + 1 + 6 + 381 + 7 + 80 + 3 + 6 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 6562337630436 + 375419300547600 = 2561706^2 + 19375740^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381981638178037) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 248706970 + ... + 250238126.

It is an arithmetic number, because the mean of its divisors is an integer number (6425617087113).

Almost surely, 2^{381981638178036} is an apocalyptic number.

381981638178036 is a gapful number since it is divisible by the number (36) 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 381981638178036, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (539751835317492).

381981638178036 is an abundant number, since it is smaller than the sum of its proper divisors (697522032456948).

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

381981638178036 is a wasteful number, since it uses less digits than its factorization.

381981638178036 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1537773 (or 1537756 counting only the distinct ones).

The product of its (nonzero) digits is 250822656, while the sum is 72.

The spelling of 381981638178036 in words is "three hundred eighty-one trillion, nine hundred eighty-one billion, six hundred thirty-eight million, one hundred seventy-eight thousand, thirty-six".