82431577881 has 135 divisors (see below), whose sum is σ = 137743287759. Its totient is φ = 49116310848.

The previous prime is 82431577859. The next prime is 82431577889. The reversal of 82431577881 is 18877513428.

The square root of 82431577881 is 287109.

It is a perfect power (a square), and thus also a powerful number.

82431577881 is a `hidden beast` number, since 82 + 431 + 57 + 7 + 8 + 81 = 666.

It can be written as a sum of positive squares in only one way, i.e., 46792179225 + 35639398656 = 216315^2 + 188784^2 .

It is not a de Polignac number, because 82431577881 - 2⁹ = 82431577369 is a prime.

It is a super-2 number, since 2×82431577881² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (82431577889) 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 134 ways as a sum of consecutive naturals, for example, 1129199661 + ... + 1129199733.

Almost surely, 2^82431577881 is an apocalyptic number.

82431577881 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

82431577881 is the 287109-th square number.

82431577881 is the 143555-th centered octagonal number.

It is an amenable number.

82431577881 is a deficient number, since it is larger than the sum of its proper divisors (55311709878).

82431577881 is an equidigital number, since it uses as much as digits as its factorization.

82431577881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242 (or 118 counting only the distinct ones).

The product of its digits is 3010560, while the sum is 54.

The spelling of 82431577881 in words is "eighty-two billion, four hundred thirty-one million, five hundred seventy-seven thousand, eight hundred eighty-one".