81964116 has 48 divisors (see below), whose sum is σ = 228849600. Its totient is φ = 25219296.

The previous prime is 81964109. The next prime is 81964117. The reversal of 81964116 is 61146918.

It is a happy number.

81964116 is a `hidden beast` number, since 8 + 1 + 9 + 641 + 1 + 6 = 666.

It is a super-3 number, since 3×81964116³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81964117) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27786 + ... + 30593.

It is an arithmetic number, because the mean of its divisors is an integer number (4767700).

Almost surely, 2^81964116 is an apocalyptic number.

It is an amenable number.

81964116 is an abundant number, since it is smaller than the sum of its proper divisors (146885484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81964116 is a wasteful number, since it uses less digits than its factorization.

81964116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58405 (or 58397 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 81964116 is about 9053.4035588833. The cubic root of 81964116 is about 434.3847664143.

The spelling of 81964116 in words is "eighty-one million, nine hundred sixty-four thousand, one hundred sixteen".