81457384008 has 384 divisors, whose sum is σ = 294687227520. Its totient is φ = 18380759040.

The previous prime is 81457383971. The next prime is 81457384009. The reversal of 81457384008 is 80048375418.

It is not an unprimeable number, because it can be changed into a prime (81457384009) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2844610 + ... + 2873102.

It is an arithmetic number, because the mean of its divisors is an integer number (767414655).

Almost surely, 2^81457384008 is an apocalyptic number.

81457384008 is a gapful number since it is divisible by the number (88) 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 81457384008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147343613760).

81457384008 is an abundant number, since it is smaller than the sum of its proper divisors (213229843512).

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

81457384008 is a wasteful number, since it uses less digits than its factorization.

81457384008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28557 (or 28546 counting only the distinct ones).

The product of its (nonzero) digits is 860160, while the sum is 48.

The spelling of 81457384008 in words is "eighty-one billion, four hundred fifty-seven million, three hundred eighty-four thousand, eight".