81844789901 has 8 divisors (see below), whose sum is σ = 95712179904. Its totient is φ = 68521219200.

The previous prime is 81844789889. The next prime is 81844789927. The reversal of 81844789901 is 10998744818.

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

It is not a de Polignac number, because 81844789901 - 2⁶ = 81844789837 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 (81844789951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 135954500 + ... + 135955101.

It is an arithmetic number, because the mean of its divisors is an integer number (11964022488).

Almost surely, 2^81844789901 is an apocalyptic number.

It is an amenable number.

81844789901 is a deficient number, since it is larger than the sum of its proper divisors (13867390003).

81844789901 is a wasteful number, since it uses less digits than its factorization.

81844789901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271909651.

The product of its (nonzero) digits is 4644864, while the sum is 59.

The spelling of 81844789901 in words is "eighty-one billion, eight hundred forty-four million, seven hundred eighty-nine thousand, nine hundred one".