81824132 has 12 divisors (see below), whose sum is σ = 154207116. Its totient is φ = 37764960.

The previous prime is 81824129. The next prime is 81824137. The reversal of 81824132 is 23142818.

It can be written as a sum of positive squares in 2 ways, for example, as 47554816 + 34269316 = 6896^2 + 5854^2 .

It is a junction number, because it is equal to n+sod(n) for n = 81824095 and 81824104.

It is not an unprimeable number, because it can be changed into a prime (81824137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 786719 + ... + 786822.

It is an arithmetic number, because the mean of its divisors is an integer number (12850593).

Almost surely, 2^81824132 is an apocalyptic number.

It is an amenable number.

81824132 is a deficient number, since it is larger than the sum of its proper divisors (72382984).

81824132 is a wasteful number, since it uses less digits than its factorization.

81824132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1573558 (or 1573556 counting only the distinct ones).

The product of its digits is 3072, while the sum is 29.

The square root of 81824132 is about 9045.6692400286. The cubic root of 81824132 is about 434.1373346936.

The spelling of 81824132 in words is "eighty-one million, eight hundred twenty-four thousand, one hundred thirty-two".