81412020 has 96 divisors (see below), whose sum is σ = 255830400. Its totient is φ = 21491712.

The previous prime is 81412013. The next prime is 81412027. The reversal of 81412020 is 2021418.

It is an interprime number because it is at equal distance from previous prime (81412013) and next prime (81412027).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 81411984 and 81412002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81412027) 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, 57076 + ... + 58484.

It is an arithmetic number, because the mean of its divisors is an integer number (2664900).

Almost surely, 2^81412020 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 81412020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127915200).

81412020 is an abundant number, since it is smaller than the sum of its proper divisors (174418380).

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

81412020 is a wasteful number, since it uses less digits than its factorization.

81412020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1534 (or 1526 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 81412020 is about 9022.8609653480. The cubic root of 81412020 is about 433.4072549762.

Adding to 81412020 its reverse (2021418), we get a palindrome (83433438).

The spelling of 81412020 in words is "eighty-one million, four hundred twelve thousand, twenty".