81375788469 has 12 divisors (see below), whose sum is σ = 110144658624. Its totient is φ = 53440807464.

The previous prime is 81375788383. The next prime is 81375788531. The reversal of 81375788469 is 96488757318.

It is not a de Polignac number, because 81375788469 - 2⁹ = 81375787957 is a prime.

It is a super-2 number, since 2×81375788469² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81375788069) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3007837 + ... + 3034770.

It is an arithmetic number, because the mean of its divisors is an integer number (9178721552).

Almost surely, 2^81375788469 is an apocalyptic number.

It is an amenable number.

81375788469 is a deficient number, since it is larger than the sum of its proper divisors (28768870155).

81375788469 is an equidigital number, since it uses as much as digits as its factorization.

81375788469 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6042744 (or 6042677 counting only the distinct ones).

The product of its digits is 81285120, while the sum is 66.

The spelling of 81375788469 in words is "eighty-one billion, three hundred seventy-five million, seven hundred eighty-eight thousand, four hundred sixty-nine".