81967575 has 12 divisors (see below), whose sum is σ = 135519848. Its totient is φ = 43716000.

The previous prime is 81967559. The next prime is 81967597. The reversal of 81967575 is 57576918.

It is not a de Polignac number, because 81967575 - 2⁴ = 81967559 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 546376 + ... + 546525.

Almost surely, 2^81967575 is an apocalyptic number.

81967575 is a deficient number, since it is larger than the sum of its proper divisors (53552273).

81967575 is a wasteful number, since it uses less digits than its factorization.

81967575 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1092914 (or 1092909 counting only the distinct ones).

The product of its digits is 529200, while the sum is 48.

The square root of 81967575 is about 9053.5945899957. The cubic root of 81967575 is about 434.3908768760.

The spelling of 81967575 in words is "eighty-one million, nine hundred sixty-seven thousand, five hundred seventy-five".