81194849118 has 64 divisors (see below), whose sum is σ = 182810234880. Its totient is φ = 26710172064.

The previous prime is 81194849117. The next prime is 81194849119.

81194849118 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (81194849117) and next prime (81194849119).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81194849117) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1604755 + ... + 1654577.

It is an arithmetic number, because the mean of its divisors is an integer number (2856409920).

Almost surely, 2^81194849118 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81194849118, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91405117440).

81194849118 is an abundant number, since it is smaller than the sum of its proper divisors (101615385762).

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

81194849118 is a wasteful number, since it uses less digits than its factorization.

81194849118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50230 (or 50224 counting only the distinct ones).

The product of its digits is 663552, while the sum is 54.

The spelling of 81194849118 in words is "eighty-one billion, one hundred ninety-four million, eight hundred forty-nine thousand, one hundred eighteen".