81438300 has 108 divisors (see below), whose sum is σ = 261608256. Its totient is φ = 21177600.

The previous prime is 81438283. The next prime is 81438307. The reversal of 81438300 is 383418.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81438307) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 35797 + ... + 38003.

Almost surely, 2^81438300 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 81438300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130804128).

81438300 is an abundant number, since it is smaller than the sum of its proper divisors (180169956).

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

81438300 is a wasteful number, since it uses less digits than its factorization.

81438300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2268 (or 2258 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 81438300 is about 9024.3171486822. The cubic root of 81438300 is about 433.4538849346.

The spelling of 81438300 in words is "eighty-one million, four hundred thirty-eight thousand, three hundred".