81418965376 has 256 divisors, whose sum is σ = 200618496000. Its totient is φ = 32140634112.

The previous prime is 81418965337. The next prime is 81418965401. The reversal of 81418965376 is 67356981418.

It is a self number, because there is not a number n which added to its sum of digits gives 81418965376.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 103454455 + ... + 103455241.

It is an arithmetic number, because the mean of its divisors is an integer number (783666000).

Almost surely, 2^81418965376 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81418965376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100309248000).

81418965376 is an abundant number, since it is smaller than the sum of its proper divisors (119199530624).

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

81418965376 is a wasteful number, since it uses less digits than its factorization.

81418965376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 989 (or 977 counting only the distinct ones).

The product of its digits is 8709120, while the sum is 58.

The spelling of 81418965376 in words is "eighty-one billion, four hundred eighteen million, nine hundred sixty-five thousand, three hundred seventy-six".