81424622500 has 135 divisors (see below), whose sum is σ = 193250047221. Its totient is φ = 29995992000.

The previous prime is 81424622459. The next prime is 81424622527. The reversal of 81424622500 is 522642418.

The square root of 81424622500 is 285350.

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

It can be written as a sum of positive squares in 7 ways, for example, as 80425556836 + 999065664 = 283594^2 + 31608^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 185477281 + ... + 185477719.

Almost surely, 2^81424622500 is an apocalyptic number.

81424622500 is the 285350-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81424622500

81424622500 is an abundant number, since it is smaller than the sum of its proper divisors (111825424721).

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

81424622500 is an equidigital number, since it uses as much as digits as its factorization.

81424622500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 928 (or 459 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 34.

The spelling of 81424622500 in words is "eighty-one billion, four hundred twenty-four million, six hundred twenty-two thousand, five hundred".