81545254518 has 128 divisors (see below), whose sum is σ = 203740250112. Its totient is φ = 21185110656.

The previous prime is 81545254493. The next prime is 81545254537.

81545254518 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 16629255 + ... + 16634157.

It is an arithmetic number, because the mean of its divisors is an integer number (1591720704).

Almost surely, 2^81545254518 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81545254518, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101870125056).

81545254518 is an abundant number, since it is smaller than the sum of its proper divisors (122194995594).

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

81545254518 is a wasteful number, since it uses less digits than its factorization.

81545254518 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5378.

The product of its digits is 1280000, while the sum is 48.

The spelling of 81545254518 in words is "eighty-one billion, five hundred forty-five million, two hundred fifty-four thousand, five hundred eighteen".