81593450401 has 2 divisors, whose sum is σ = 81593450402. Its totient is φ = 81593450400.

The previous prime is 81593450333. The next prime is 81593450443. The reversal of 81593450401 is 10405439518.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57343486225 + 24249964176 = 239465^2 + 155724^2 .

It is a cyclic number.

It is not a de Polignac number, because 81593450401 - 2¹³ = 81593442209 is a prime.

It is a super-2 number, since 2×81593450401² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81593450101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40796725200 + 40796725201.

It is an arithmetic number, because the mean of its divisors is an integer number (40796725201).

Almost surely, 2^81593450401 is an apocalyptic number.

It is an amenable number.

81593450401 is a deficient number, since it is larger than the sum of its proper divisors (1).

81593450401 is an equidigital number, since it uses as much as digits as its factorization.

81593450401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 86400, while the sum is 40.

Adding to 81593450401 its reverse (10405439518), we get a palindrome (91998889919).

The spelling of 81593450401 in words is "eighty-one billion, five hundred ninety-three million, four hundred fifty thousand, four hundred one".