81946608 has 80 divisors (see below), whose sum is σ = 222604800. Its totient is φ = 25926912.

The previous prime is 81946597. The next prime is 81946619. The reversal of 81946608 is 80664918.

It is an interprime number because it is at equal distance from previous prime (81946597) and next prime (81946619).

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 81946608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 219510 + ... + 219882.

It is an arithmetic number, because the mean of its divisors is an integer number (2782560).

Almost surely, 2^81946608 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 81946608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111302400).

81946608 is an abundant number, since it is smaller than the sum of its proper divisors (140658192).

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

81946608 is a wasteful number, since it uses less digits than its factorization.

81946608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 606 (or 600 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 81946608 is about 9052.4365780711. The cubic root of 81946608 is about 434.3538351953.

The spelling of 81946608 in words is "eighty-one million, nine hundred forty-six thousand, six hundred eight".