81285428108988 has 96 divisors (see below), whose sum is σ = 211322488608000. Its totient is φ = 27020263217472.

The previous prime is 81285428108977. The next prime is 81285428108999. The reversal of 81285428108988 is 88980182458218.

81285428108988 is a `hidden beast` number, since 8 + 1 + 2 + 8 + 5 + 428 + 108 + 98 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (81285428108977) and next prime (81285428108999).

It is a super-2 number, since 2×81285428108988² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 527603095 + ... + 527757137.

It is an arithmetic number, because the mean of its divisors is an integer number (2201275923000).

Almost surely, 2^{81285428108988} is an apocalyptic number.

It is an amenable number.

81285428108988 is an abundant number, since it is smaller than the sum of its proper divisors (130037060499012).

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

81285428108988 is a wasteful number, since it uses less digits than its factorization.

81285428108988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167528 (or 167520 counting only the distinct ones).

The product of its (nonzero) digits is 188743680, while the sum is 72.

The spelling of 81285428108988 in words is "eighty-one trillion, two hundred eighty-five billion, four hundred twenty-eight million, one hundred eight thousand, nine hundred eighty-eight".