81515168201712 has 160 divisors (see below), whose sum is σ = 244770433689600. Its totient is φ = 22892723691264.

The previous prime is 81515168201693. The next prime is 81515168201713. The reversal of 81515168201712 is 21710286151518.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81515168201713) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 179358663 + ... + 179812569.

It is an arithmetic number, because the mean of its divisors is an integer number (1529815210560).

Almost surely, 2^{81515168201712} 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 81515168201712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122385216844800).

81515168201712 is an abundant number, since it is smaller than the sum of its proper divisors (163255265487888).

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

81515168201712 is a wasteful number, since it uses less digits than its factorization.

81515168201712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463043 (or 463037 counting only the distinct ones).

The product of its (nonzero) digits is 268800, while the sum is 48.

The spelling of 81515168201712 in words is "eighty-one trillion, five hundred fifteen billion, one hundred sixty-eight million, two hundred one thousand, seven hundred twelve".