81437681003952 has 320 divisors, whose sum is σ = 267882584417280. Its totient is φ = 20735596449792.

The previous prime is 81437681003941. The next prime is 81437681003999. The reversal of 81437681003952 is 25930018673418.

It is a junction number, because it is equal to n+sod(n) for n = 81437681003892 and 81437681003901.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1935147103 + ... + 1935189185.

It is an arithmetic number, because the mean of its divisors is an integer number (837133076304).

It is a 2-persistent number, because it is pandigital, and so is 2⋅81437681003952 = 162875362007904, but 3⋅81437681003952 = 244313043011856 is not.

Almost surely, 2^{81437681003952} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81437681003952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133941292208640).

81437681003952 is an abundant number, since it is smaller than the sum of its proper divisors (186444903413328).

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

81437681003952 is a wasteful number, since it uses less digits than its factorization.

81437681003952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57420 (or 57414 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 57.

The spelling of 81437681003952 in words is "eighty-one trillion, four hundred thirty-seven billion, six hundred eighty-one million, three thousand, nine hundred fifty-two".