81738594160 has 80 divisors (see below), whose sum is σ = 199732216320. Its totient is φ = 31048807680.

The previous prime is 81738594121. The next prime is 81738594167. The reversal of 81738594160 is 6149583718.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×81738594160² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81738594098 and 81738594107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81738594167) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95965 + ... + 415555.

It is an arithmetic number, because the mean of its divisors is an integer number (2496652704).

Almost surely, 2^81738594160 is an apocalyptic number.

81738594160 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81738594160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99866108160).

81738594160 is an abundant number, since it is smaller than the sum of its proper divisors (117993622160).

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

81738594160 is a wasteful number, since it uses less digits than its factorization.

81738594160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319766 (or 319760 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 52.

The spelling of 81738594160 in words is "eighty-one billion, seven hundred thirty-eight million, five hundred ninety-four thousand, one hundred sixty".