81983136 has 48 divisors (see below), whose sum is σ = 216052704. Its totient is φ = 27220224.

The previous prime is 81983131. The next prime is 81983141. The reversal of 81983136 is 63138918.

It is an interprime number because it is at equal distance from previous prime (81983131) and next prime (81983141).

It is a tau number, because it is divible by the number of its divisors (48).

It is a junction number, because it is equal to n+sod(n) for n = 81983094 and 81983103.

It is not an unprimeable number, because it can be changed into a prime (81983131) 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 7 ways as a sum of consecutive naturals, for example, 25051 + ... + 28133.

It is an arithmetic number, because the mean of its divisors is an integer number (4501098).

Almost surely, 2^81983136 is an apocalyptic number.

It is an amenable number.

81983136 is an abundant number, since it is smaller than the sum of its proper divisors (134069568).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81983136 is a wasteful number, since it uses less digits than its factorization.

81983136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3373 (or 3365 counting only the distinct ones).

The product of its digits is 31104, while the sum is 39.

The square root of 81983136 is about 9054.4539316294. The cubic root of 81983136 is about 434.4183638781.

The spelling of 81983136 in words is "eighty-one million, nine hundred eighty-three thousand, one hundred thirty-six".