81224430001 has 27 divisors (see below), whose sum is σ = 96724232577. Its totient is φ = 68126160960.

The previous prime is 81224429989. The next prime is 81224430029. The reversal of 81224430001 is 10003442218.

The square root of 81224430001 is 284999.

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

It can be written as a sum of positive squares in 4 ways, for example, as 1801917601 + 79422512400 = 42449^2 + 281820^2 .

It is a de Polignac number, because none of the positive numbers 2^k-81224430001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81224430041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 40753861 + ... + 40755853.

Almost surely, 2^81224430001 is an apocalyptic number.

81224430001 is the 284999-th square number.

81224430001 is the 142500-th centered octagonal number.

It is an amenable number.

81224430001 is a deficient number, since it is larger than the sum of its proper divisors (15499802576).

81224430001 is an equidigital number, since it uses as much as digits as its factorization.

81224430001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4034 (or 2017 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 25.

Multiplying 81224430001 by its sum of digits (25), we get a square (2030610750025 = 1424995²).

Adding to 81224430001 its reverse (10003442218), we get a palindrome (91227872219).

It can be divided in two parts, 81224 and 430001, that added together give a square (511225 = 715²).

The spelling of 81224430001 in words is "eighty-one billion, two hundred twenty-four million, four hundred thirty thousand, one".