81481932 has 36 divisors (see below), whose sum is σ = 235392976. Its totient is φ = 23280480.

The previous prime is 81481921. The next prime is 81481949. The reversal of 81481932 is 23918418.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 161419 + ... + 161922.

Almost surely, 2^81481932 is an apocalyptic number.

It is an amenable number.

81481932 is an abundant number, since it is smaller than the sum of its proper divisors (153911044).

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

81481932 is a wasteful number, since it uses less digits than its factorization.

81481932 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323358 (or 323353 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 81481932 is about 9026.7342931982. The cubic root of 81481932 is about 433.5312812921.

The spelling of 81481932 in words is "eighty-one million, four hundred eighty-one thousand, nine hundred thirty-two".