81832761 has 30 divisors (see below), whose sum is σ = 125506766. Its totient is φ = 53136000.

The previous prime is 81832757. The next prime is 81832783. The reversal of 81832761 is 16723818.

It can be written as a sum of positive squares in 3 ways, for example, as 20736 + 81812025 = 144^2 + 9045^2 .

It is not a de Polignac number, because 81832761 - 2² = 81832757 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81832711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 135861 + ... + 136461.

Almost surely, 2^81832761 is an apocalyptic number.

81832761 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

It is an amenable number.

81832761 is a deficient number, since it is larger than the sum of its proper divisors (43674005).

81832761 is an equidigital number, since it uses as much as digits as its factorization.

81832761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 695 (or 645 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 81832761 is about 9046.1461960329. The cubic root of 81832761 is about 434.1525952257.

The spelling of 81832761 in words is "eighty-one million, eight hundred thirty-two thousand, seven hundred sixty-one".