81831953 has 8 divisors (see below), whose sum is σ = 97588608. Its totient is φ = 67091904.

The previous prime is 81831929. The next prime is 81832019. The reversal of 81831953 is 35913818.

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 81831953 - 2⁶ = 81831889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81831923) 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, 253976 + ... + 254297.

It is an arithmetic number, because the mean of its divisors is an integer number (12198576).

Almost surely, 2^81831953 is an apocalyptic number.

It is an amenable number.

81831953 is a deficient number, since it is larger than the sum of its proper divisors (15756655).

81831953 is a wasteful number, since it uses less digits than its factorization.

81831953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 508303.

The product of its digits is 25920, while the sum is 38.

The square root of 81831953 is about 9046.1015360209. The cubic root of 81831953 is about 434.1511663096.

The spelling of 81831953 in words is "eighty-one million, eight hundred thirty-one thousand, nine hundred fifty-three".