81824602500 has 135 divisors (see below), whose sum is σ = 258595884547. Its totient is φ = 21808452000.

The previous prime is 81824602469. The next prime is 81824602501. The reversal of 81824602500 is 520642818.

The square root of 81824602500 is 286050.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 6415048836 + 75409553664 = 80094^2 + 274608^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81824602501) 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 44 ways as a sum of consecutive naturals, for example, 42906547 + ... + 42908453.

Almost surely, 2^81824602500 is an apocalyptic number.

81824602500 is the 286050-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81824602500

81824602500 is an abundant number, since it is smaller than the sum of its proper divisors (176771282047).

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

81824602500 is an equidigital number, since it uses as much as digits as its factorization.

81824602500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3844 (or 1917 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

Multiplying 81824602500 by its sum of digits (36), we get a square (2945685690000 = 1716300²).

81824602500 divided by its sum of digits (36) gives a square (2272905625 = 47675²).

The spelling of 81824602500 in words is "eighty-one billion, eight hundred twenty-four million, six hundred two thousand, five hundred".