81963071 has 2 divisors, whose sum is σ = 81963072. Its totient is φ = 81963070.

The previous prime is 81963067. The next prime is 81963097. The reversal of 81963071 is 17036918.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81963071 - 2² = 81963067 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81963671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40981535 + 40981536.

It is an arithmetic number, because the mean of its divisors is an integer number (40981536).

Almost surely, 2^81963071 is an apocalyptic number.

81963071 is a deficient number, since it is larger than the sum of its proper divisors (1).

81963071 is an equidigital number, since it uses as much as digits as its factorization.

81963071 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 81963071 is about 9053.3458455976. The cubic root of 81963071 is about 434.3829203462.

Adding to 81963071 its reverse (17036918), we get a palindrome (98999989).

The spelling of 81963071 in words is "eighty-one million, nine hundred sixty-three thousand, seventy-one".