81046400 has 192 divisors, whose sum is σ = 222604800. Its totient is φ = 29030400.

The previous prime is 81046397. The next prime is 81046403. The reversal of 81046400 is 464018.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (81046397) and next prime (81046403).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81046403) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 1884779 + ... + 1884821.

It is an arithmetic number, because the mean of its divisors is an integer number (1159400).

Almost surely, 2^81046400 is an apocalyptic number.

81046400 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 81046400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111302400).

81046400 is an abundant number, since it is smaller than the sum of its proper divisors (141558400).

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

81046400 is a wasteful number, since it uses less digits than its factorization.

81046400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117 (or 100 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 81046400 is about 9002.5774087202. The cubic root of 81046400 is about 432.7574730748.

The spelling of 81046400 in words is "eighty-one million, forty-six thousand, four hundred".