81018974453759 has 2 divisors, whose sum is σ = 81018974453760. Its totient is φ = 81018974453758.

The previous prime is 81018974453717. The next prime is 81018974453783. The reversal of 81018974453759 is 95735447981018.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81018974453759 - 2⁸ = 81018974453503 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 81018974453692 and 81018974453701.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81018974455759) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40509487226879 + 40509487226880.

It is an arithmetic number, because the mean of its divisors is an integer number (40509487226880).

Almost surely, 2^{81018974453759} is an apocalyptic number.

81018974453759 is a deficient number, since it is larger than the sum of its proper divisors (1).

81018974453759 is an equidigital number, since it uses as much as digits as its factorization.

81018974453759 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 304819200, while the sum is 71.

The spelling of 81018974453759 in words is "eighty-one trillion, eighteen billion, nine hundred seventy-four million, four hundred fifty-three thousand, seven hundred fifty-nine".