81764316 has 30 divisors (see below), whose sum is σ = 213748920. Its totient is φ = 27254664.

The previous prime is 81764303. The next prime is 81764317. The reversal of 81764316 is 61346718.

81764316 is a `hidden beast` number, since 8 + 1 + 7 + 643 + 1 + 6 = 666.

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 (81764317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 125856 + ... + 126503.

It is an arithmetic number, because the mean of its divisors is an integer number (7124964).

Almost surely, 2^81764316 is an apocalyptic number.

It is an amenable number.

81764316 is an abundant number, since it is smaller than the sum of its proper divisors (131984604).

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

81764316 is a wasteful number, since it uses less digits than its factorization.

81764316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252375 (or 252364 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 81764316 is about 9042.3623019651. The cubic root of 81764316 is about 434.0315195807.

The spelling of 81764316 in words is "eighty-one million, seven hundred sixty-four thousand, three hundred sixteen".