81295400 has 48 divisors (see below), whose sum is σ = 189764640. Its totient is φ = 32388800.

The previous prime is 81295387. The next prime is 81295427. The reversal of 81295400 is 459218.

It is a super-2 number, since 2×81295400² = 13217884122320000, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61547 + ... + 62853.

It is an arithmetic number, because the mean of its divisors is an integer number (3953430).

Almost surely, 2^81295400 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 81295400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94882320).

81295400 is an abundant number, since it is smaller than the sum of its proper divisors (108469240).

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

81295400 is a wasteful number, since it uses less digits than its factorization.

81295400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1634 (or 1625 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 81295400 is about 9016.3961758565. The cubic root of 81295400 is about 433.2002089427.

The spelling of 81295400 in words is "eighty-one million, two hundred ninety-five thousand, four hundred".