81425412 has 72 divisors (see below), whose sum is σ = 224733600. Its totient is φ = 25707456.

The previous prime is 81425411. The next prime is 81425413. The reversal of 81425412 is 21452418.

81425412 is a `hidden beast` number, since 81 + 42 + 541 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (81425411) and next prime (81425413).

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

It is not an unprimeable number, because it can be changed into a prime (81425411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16264 + ... + 20672.

It is an arithmetic number, because the mean of its divisors is an integer number (3121300).

Almost surely, 2^81425412 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 81425412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112366800).

81425412 is an abundant number, since it is smaller than the sum of its proper divisors (143308188).

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

81425412 is a wasteful number, since it uses less digits than its factorization.

81425412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4447 (or 4433 counting only the distinct ones).

The product of its digits is 2560, while the sum is 27.

The square root of 81425412 is about 9023.6030497801. The cubic root of 81425412 is about 433.4310183457.

The spelling of 81425412 in words is "eighty-one million, four hundred twenty-five thousand, four hundred twelve".