81724086031 has 12 divisors (see below), whose sum is σ = 95732554096. Its totient is φ = 68340689280.

The previous prime is 81724086023. The next prime is 81724086049. The reversal of 81724086031 is 13068042718.

It is not a de Polignac number, because 81724086031 - 2³ = 81724086023 is a prime.

It is a super-2 number, since 2×81724086031² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81724086061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3460830 + ... + 3484363.

Almost surely, 2^81724086031 is an apocalyptic number.

81724086031 is a deficient number, since it is larger than the sum of its proper divisors (14008468065).

81724086031 is an equidigital number, since it uses as much as digits as its factorization.

81724086031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6945282 (or 6945241 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The spelling of 81724086031 in words is "eighty-one billion, seven hundred twenty-four million, eighty-six thousand, thirty-one".