81738020 has 96 divisors (see below), whose sum is σ = 213900288. Its totient is φ = 25546752.

The previous prime is 81738001. The next prime is 81738043. The reversal of 81738020 is 2083718.

It is a super-2 number, since 2×81738020² = 13362207827040800, which contains 22 as substring.

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, 176309 + ... + 176771.

It is an arithmetic number, because the mean of its divisors is an integer number (2228128).

Almost surely, 2^81738020 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 81738020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106950144).

81738020 is an abundant number, since it is smaller than the sum of its proper divisors (132162268).

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

81738020 is a wasteful number, since it uses less digits than its factorization.

81738020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 589 (or 587 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 81738020 is about 9040.9081402257. The cubic root of 81738020 is about 433.9849853584.

The spelling of 81738020 in words is "eighty-one million, seven hundred thirty-eight thousand, twenty".