81161116 has 12 divisors (see below), whose sum is σ = 143411632. Its totient is φ = 40186368.

The previous prime is 81161083. The next prime is 81161117. The reversal of 81161116 is 61116118.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81161117) 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, 98085 + ... + 98908.

Almost surely, 2^81161116 is an apocalyptic number.

It is an amenable number.

81161116 is a deficient number, since it is larger than the sum of its proper divisors (62250516).

81161116 is a wasteful number, since it uses less digits than its factorization.

81161116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197100 (or 197098 counting only the distinct ones).

The product of its digits is 288, while the sum is 25.

The square root of 81161116 is about 9008.9464422872. The cubic root of 81161116 is about 432.9615569986.

The spelling of 81161116 in words is "eighty-one million, one hundred sixty-one thousand, one hundred sixteen".