81447336 has 32 divisors (see below), whose sum is σ = 226243200. Its totient is φ = 27149040.

The previous prime is 81447299. The next prime is 81447343. The reversal of 81447336 is 63374418.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 81447336.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 188320 + ... + 188751.

It is an arithmetic number, because the mean of its divisors is an integer number (7070100).

Almost surely, 2^81447336 is an apocalyptic number.

It is an amenable number.

81447336 is an abundant number, since it is smaller than the sum of its proper divisors (144795864).

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

81447336 is a wasteful number, since it uses less digits than its factorization.

81447336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377086 (or 377076 counting only the distinct ones).

The product of its digits is 48384, while the sum is 36.

The square root of 81447336 is about 9024.8177820940. The cubic root of 81447336 is about 433.4699156575.

The spelling of 81447336 in words is "eighty-one million, four hundred forty-seven thousand, three hundred thirty-six".