81902471003136 has 528 divisors, whose sum is σ = 282738046291200. Its totient is φ = 23352467152896.

The previous prime is 81902471003107. The next prime is 81902471003159. The reversal of 81902471003136 is 63130017420918.

81902471003136 is a `hidden beast` number, since 8 + 1 + 90 + 247 + 1 + 0 + 0 + 313 + 6 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 81902471003091 and 81902471003100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 659702155 + ... + 659826293.

Almost surely, 2^{81902471003136} 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 81902471003136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141369023145600).

81902471003136 is an abundant number, since it is smaller than the sum of its proper divisors (200835575288064).

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

81902471003136 is a wasteful number, since it uses less digits than its factorization.

81902471003136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124669 (or 124638 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 81902471003136 in words is "eighty-one trillion, nine hundred two billion, four hundred seventy-one million, three thousand, one hundred thirty-six".