81444101 has 4 divisors (see below), whose sum is σ = 81830304. Its totient is φ = 81057900.

The previous prime is 81444049. The next prime is 81444109. The reversal of 81444101 is 10144418.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81444101 - 2¹⁰ = 81443077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81444109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192785 + ... + 193206.

It is an arithmetic number, because the mean of its divisors is an integer number (20457576).

Almost surely, 2^81444101 is an apocalyptic number.

It is an amenable number.

81444101 is a deficient number, since it is larger than the sum of its proper divisors (386203).

81444101 is a wasteful number, since it uses less digits than its factorization.

81444101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386202.

The product of its (nonzero) digits is 512, while the sum is 23.

The square root of 81444101 is about 9024.6385523189. The cubic root of 81444101 is about 433.4641765962.

Adding to 81444101 its reverse (10144418), we get a palindrome (91588519).

The spelling of 81444101 in words is "eighty-one million, four hundred forty-four thousand, one hundred one".