81436398 has 8 divisors (see below), whose sum is σ = 162872808. Its totient is φ = 27145464.

The previous prime is 81436393. The next prime is 81436417. The reversal of 81436398 is 89363418.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

81436398 is an admirable number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81436393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6786361 + ... + 6786372.

It is an arithmetic number, because the mean of its divisors is an integer number (20359101).

Almost surely, 2^81436398 is an apocalyptic number.

81436398 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81436398 is a wasteful number, since it uses less digits than its factorization.

81436398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13572738.

The product of its digits is 124416, while the sum is 42.

The square root of 81436398 is about 9024.2117661323. The cubic root of 81436398 is about 433.4505104548.

It can be divided in two parts, 8143 and 6398, that added together give a palindrome (14541).

The spelling of 81436398 in words is "eighty-one million, four hundred thirty-six thousand, three hundred ninety-eight".