81752020 has 48 divisors (see below), whose sum is σ = 197100288. Its totient is φ = 27901440.

The previous prime is 81752009. The next prime is 81752029. The reversal of 81752020 is 2025718.

81752020 is nontrivially palindromic in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81752029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32529 + ... + 34951.

It is an arithmetic number, because the mean of its divisors is an integer number (4106256).

Almost surely, 2^81752020 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 81752020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98550144).

81752020 is an abundant number, since it is smaller than the sum of its proper divisors (115348268).

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

81752020 is a wasteful number, since it uses less digits than its factorization.

81752020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2680 (or 2678 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 81752020 is about 9041.6823655778. The cubic root of 81752020 is about 434.0097614375.

Adding to 81752020 its reverse (2025718), we get a palindrome (83777738).

The spelling of 81752020 in words is "eighty-one million, seven hundred fifty-two thousand, twenty".