81495100 has 36 divisors (see below), whose sum is σ = 178222968. Its totient is φ = 32344000.

The previous prime is 81495097. The next prime is 81495101. The reversal of 81495100 is 159418.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81495101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9990 + ... + 16210.

It is an arithmetic number, because the mean of its divisors is an integer number (4950638).

Almost surely, 2^81495100 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 81495100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89111484).

81495100 is an abundant number, since it is smaller than the sum of its proper divisors (96727868).

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

81495100 is a wasteful number, since it uses less digits than its factorization.

81495100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6366 (or 6359 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 81495100 is about 9027.4636526546. The cubic root of 81495100 is about 433.5546338411.

The spelling of 81495100 in words is "eighty-one million, four hundred ninety-five thousand, one hundred".