81544914 has 64 divisors (see below), whose sum is σ = 199687680. Its totient is φ = 24460560.

The previous prime is 81544909. The next prime is 81544919. The reversal of 81544914 is 41944518.

It is an interprime number because it is at equal distance from previous prime (81544909) and next prime (81544919).

It is not an unprimeable number, because it can be changed into a prime (81544919) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 62917 + ... + 64199.

It is an arithmetic number, because the mean of its divisors is an integer number (3120120).

Almost surely, 2^81544914 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81544914, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99843840).

81544914 is an abundant number, since it is smaller than the sum of its proper divisors (118142766).

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

81544914 is a wasteful number, since it uses less digits than its factorization.

81544914 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1412 (or 1406 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 81544914 is about 9030.2222564010. Note that the first 4 decimals coincide. The cubic root of 81544914 is about 433.6429528182.

The spelling of 81544914 in words is "eighty-one million, five hundred forty-four thousand, nine hundred fourteen".