81956132 has 12 divisors (see below), whose sum is σ = 143571120. Its totient is φ = 40935816.

The previous prime is 81956131. The next prime is 81956141. The reversal of 81956132 is 23165918.

It is a junction number, because it is equal to n+sod(n) for n = 81956092 and 81956101.

It is not an unprimeable number, because it can be changed into a prime (81956131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5978 + ... + 14129.

It is an arithmetic number, because the mean of its divisors is an integer number (11964260).

Almost surely, 2^81956132 is an apocalyptic number.

It is an amenable number.

81956132 is a deficient number, since it is larger than the sum of its proper divisors (61614988).

81956132 is a wasteful number, since it uses less digits than its factorization.

81956132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21130 (or 21128 counting only the distinct ones).

The product of its digits is 12960, while the sum is 35.

The square root of 81956132 is about 9052.9626090026. The cubic root of 81956132 is about 434.3706617030.

The spelling of 81956132 in words is "eighty-one million, nine hundred fifty-six thousand, one hundred thirty-two".