81518050080 has 120 divisors (see below), whose sum is σ = 287690830812. Its totient is φ = 21738143232.

The previous prime is 81518050063. The next prime is 81518050109. The reversal of 81518050080 is 8005081518.

It can be written as a sum of positive squares in 2 ways, for example, as 76182624144 + 5335425936 = 276012^2 + 73044^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3132027 + ... + 3157946.

Almost surely, 2^81518050080 is an apocalyptic number.

81518050080 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81518050080 is an abundant number, since it is smaller than the sum of its proper divisors (206172780732).

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

81518050080 is a wasteful number, since it uses less digits than its factorization.

81518050080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6290000 (or 6289983 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 36.

The spelling of 81518050080 in words is "eighty-one billion, five hundred eighteen million, fifty thousand, eighty".