81362400 has 288 divisors, whose sum is σ = 314979840. Its totient is φ = 17848320.

The previous prime is 81362387. The next prime is 81362417. The reversal of 81362400 is 426318.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 487117 + ... + 487283.

It is an arithmetic number, because the mean of its divisors is an integer number (1093680).

Almost surely, 2^81362400 is an apocalyptic number.

81362400 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 81362400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (157489920).

81362400 is an abundant number, since it is smaller than the sum of its proper divisors (233617440).

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

81362400 is a wasteful number, since it uses less digits than its factorization.

81362400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226 (or 213 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 81362400 is about 9020.1108640637. The cubic root of 81362400 is about 433.3191842849.

Adding to 81362400 its reverse (426318), we get a palindrome (81788718).

The spelling of 81362400 in words is "eighty-one million, three hundred sixty-two thousand, four hundred".