81018974453503 has 2 divisors, whose sum is σ = 81018974453504. Its totient is φ = 81018974453502.

The previous prime is 81018974453423. The next prime is 81018974453507. The reversal of 81018974453503 is 30535447981018.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81018974453503 - 2¹⁷ = 81018974322431 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81018974453507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40509487226751 + 40509487226752.

It is an arithmetic number, because the mean of its divisors is an integer number (40509487226752).

Almost surely, 2^{81018974453503} is an apocalyptic number.

81018974453503 is a deficient number, since it is larger than the sum of its proper divisors (1).

81018974453503 is an equidigital number, since it uses as much as digits as its factorization.

81018974453503 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14515200, while the sum is 58.

The spelling of 81018974453503 in words is "eighty-one trillion, eighteen billion, nine hundred seventy-four million, four hundred fifty-three thousand, five hundred three".