81408132 has 96 divisors (see below), whose sum is σ = 237269760. Its totient is φ = 23950080.

The previous prime is 81408101. The next prime is 81408161. The reversal of 81408132 is 23180418.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 81408096 and 81408105.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31032 + ... + 33552.

It is an arithmetic number, because the mean of its divisors is an integer number (2471560).

Almost surely, 2^81408132 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 81408132, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118634880).

81408132 is an abundant number, since it is smaller than the sum of its proper divisors (155861628).

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

81408132 is a wasteful number, since it uses less digits than its factorization.

81408132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2570 (or 2562 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 81408132 is about 9022.6455100486. The cubic root of 81408132 is about 433.4003554454.

The spelling of 81408132 in words is "eighty-one million, four hundred eight thousand, one hundred thirty-two".