81734400 has 432 divisors, whose sum is σ = 334561920. Its totient is φ = 19353600.

The previous prime is 81734399. The next prime is 81734407. The reversal of 81734400 is 443718.

It is a tau number, because it is divible by the number of its divisors (432).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81734407) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1900779 + ... + 1900821.

Almost surely, 2^81734400 is an apocalyptic number.

81734400 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 81734400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (167280960).

81734400 is an abundant number, since it is smaller than the sum of its proper divisors (252827520).

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

81734400 is a wasteful number, since it uses less digits than its factorization.

81734400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 81734400 is about 9040.7079368819. The cubic root of 81734400 is about 433.9785785119.

The spelling of 81734400 in words is "eighty-one million, seven hundred thirty-four thousand, four hundred".