81371400 has 96 divisors (see below), whose sum is σ = 275205600. Its totient is φ = 19724800.

The previous prime is 81371371. The next prime is 81371453. The reversal of 81371400 is 417318.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 436 + ... + 12764.

It is an arithmetic number, because the mean of its divisors is an integer number (2866725).

Almost surely, 2^81371400 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 81371400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137602800).

81371400 is an abundant number, since it is smaller than the sum of its proper divisors (193834200).

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

81371400 is a wasteful number, since it uses less digits than its factorization.

81371400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12359 (or 12350 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 81371400 is about 9020.6097354891. The cubic root of 81371400 is about 433.3351610705.

Adding to 81371400 its reverse (417318), we get a palindrome (81788718).

The spelling of 81371400 in words is "eighty-one million, three hundred seventy-one thousand, four hundred".