81785963 has 8 divisors (see below), whose sum is σ = 98968032. Its totient is φ = 65978496.

The previous prime is 81785917. The next prime is 81785971. The reversal of 81785963 is 36958718.

It is a happy number.

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

It is not a de Polignac number, because 81785963 - 2¹⁴ = 81769579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81785993) 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, 343520 + ... + 343757.

It is an arithmetic number, because the mean of its divisors is an integer number (12371004).

Almost surely, 2^81785963 is an apocalyptic number.

81785963 is a deficient number, since it is larger than the sum of its proper divisors (17182069).

81785963 is a wasteful number, since it uses less digits than its factorization.

81785963 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 687301.

The product of its digits is 362880, while the sum is 47.

The square root of 81785963 is about 9043.5591997841. The cubic root of 81785963 is about 434.0698193010.

It can be divided in two parts, 8178 and 5963, that added together give a palindrome (14141).

The spelling of 81785963 in words is "eighty-one million, seven hundred eighty-five thousand, nine hundred sixty-three".