81608982 has 64 divisors (see below), whose sum is σ = 202535424. Its totient is φ = 21346560.

The previous prime is 81608981. The next prime is 81608999. The reversal of 81608982 is 28980618.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81608981) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 74257 + ... + 75347.

It is an arithmetic number, because the mean of its divisors is an integer number (3164616).

Almost surely, 2^81608982 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81608982, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101267712).

81608982 is an abundant number, since it is smaller than the sum of its proper divisors (120926442).

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

81608982 is a wasteful number, since it uses less digits than its factorization.

81608982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1253.

The product of its (nonzero) digits is 55296, while the sum is 42.

The square root of 81608982 is about 9033.7689808850. The cubic root of 81608982 is about 433.7564909182.

The spelling of 81608982 in words is "eighty-one million, six hundred eight thousand, nine hundred eighty-two".