81510401518 has 24 divisors (see below), whose sum is σ = 153167899752. Its totient is φ = 32245872624.

The previous prime is 81510401513. The next prime is 81510401543.

81510401518 is nontrivially palindromic in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81510401513) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31988680 + ... + 31991227.

It is an arithmetic number, because the mean of its divisors is an integer number (6381995823).

Almost surely, 2^81510401518 is an apocalyptic number.

81510401518 is a deficient number, since it is larger than the sum of its proper divisors (71657498234).

81510401518 is a wasteful number, since it uses less digits than its factorization.

81510401518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63979936 (or 63979929 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 34.

The spelling of 81510401518 in words is "eighty-one billion, five hundred ten million, four hundred one thousand, five hundred eighteen".