81347100 has 72 divisors (see below), whose sum is σ = 242984448. Its totient is φ = 20990400.

The previous prime is 81347093. The next prime is 81347107. The reversal of 81347100 is 174318.

It is an interprime number because it is at equal distance from previous prime (81347093) and next prime (81347107).

It is a super-3 number, since 3×81347100³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81347107) 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, 4927 + ... + 13673.

It is an arithmetic number, because the mean of its divisors is an integer number (3374784).

Almost surely, 2^81347100 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 81347100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121492224).

81347100 is an abundant number, since it is smaller than the sum of its proper divisors (161637348).

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

81347100 is a wasteful number, since it uses less digits than its factorization.

81347100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8795 (or 8788 counting only the distinct ones).

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

The square root of 81347100 is about 9019.2627193136. The cubic root of 81347100 is about 433.2920210451.

The spelling of 81347100 in words is "eighty-one million, three hundred forty-seven thousand, one hundred".