81991483 has 8 divisors (see below), whose sum is σ = 94988768. Its totient is φ = 69315264.

The previous prime is 81991463. The next prime is 81991499. The reversal of 81991483 is 38419918.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81991483 - 2⁹ = 81990971 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81991433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79716 + ... + 80737.

It is an arithmetic number, because the mean of its divisors is an integer number (11873596).

Almost surely, 2^81991483 is an apocalyptic number.

81991483 is a deficient number, since it is larger than the sum of its proper divisors (12997285).

81991483 is a wasteful number, since it uses less digits than its factorization.

81991483 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160533.

The product of its digits is 62208, while the sum is 43.

The square root of 81991483 is about 9054.9148532717. The cubic root of 81991483 is about 434.4331066135.

The spelling of 81991483 in words is "eighty-one million, nine hundred ninety-one thousand, four hundred eighty-three".