81965930 has 16 divisors (see below), whose sum is σ = 148024800. Its totient is φ = 32678352.

The previous prime is 81965899. The next prime is 81965941. The reversal of 81965930 is 3956918.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10280 + ... + 16419.

It is an arithmetic number, because the mean of its divisors is an integer number (9251550).

Almost surely, 2^81965930 is an apocalyptic number.

81965930 is a deficient number, since it is larger than the sum of its proper divisors (66058870).

81965930 is a wasteful number, since it uses less digits than its factorization.

81965930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27013.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 81965930 is about 9053.5037416461. The cubic root of 81965930 is about 434.3879709392.

The spelling of 81965930 in words is "eighty-one million, nine hundred sixty-five thousand, nine hundred thirty".