81264800 has 36 divisors (see below), whose sum is σ = 198389646. Its totient is φ = 32505600.

The previous prime is 81264793. The next prime is 81264809. The reversal of 81264800 is 846218.

It can be written as a sum of positive squares in 3 ways, for example, as 58186384 + 23078416 = 7628^2 + 4804^2 .

It is not an unprimeable number, because it can be changed into a prime (81264809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 49991 + ... + 51590.

Almost surely, 2^81264800 is an apocalyptic number.

81264800 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81264800 is an abundant number, since it is smaller than the sum of its proper divisors (117124846).

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

81264800 is a wasteful number, since it uses less digits than its factorization.

81264800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101601 (or 101588 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 81264800 is about 9014.6991075687. The cubic root of 81264800 is about 433.1458492046.

The spelling of 81264800 in words is "eighty-one million, two hundred sixty-four thousand, eight hundred".