81935967 has 4 divisors (see below), whose sum is σ = 109247960. Its totient is φ = 54623976.

The previous prime is 81935963. The next prime is 81935977. The reversal of 81935967 is 76953918.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 81935967 - 2² = 81935963 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81935963) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13655992 + ... + 13655997.

It is an arithmetic number, because the mean of its divisors is an integer number (27311990).

Almost surely, 2^81935967 is an apocalyptic number.

81935967 is a deficient number, since it is larger than the sum of its proper divisors (27311993).

81935967 is a wasteful number, since it uses less digits than its factorization.

81935967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27311992.

The product of its digits is 408240, while the sum is 48.

The square root of 81935967 is about 9051.8488166783. The cubic root of 81935967 is about 434.3350336881.

The spelling of 81935967 in words is "eighty-one million, nine hundred thirty-five thousand, nine hundred sixty-seven".