81557675518 has 32 divisors (see below), whose sum is σ = 136741893120. Its totient is φ = 36159864000.

The previous prime is 81557675509. The next prime is 81557675561.

81557675518 is nontrivially palindromic in base 10.

It is a super-5 number, since 5×81557675518⁵ (a number of 56 digits) contains 55555 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8086803 + ... + 8096881.

It is an arithmetic number, because the mean of its divisors is an integer number (4273184160).

Almost surely, 2^81557675518 is an apocalyptic number.

81557675518 is a deficient number, since it is larger than the sum of its proper divisors (55184217602).

81557675518 is a wasteful number, since it uses less digits than its factorization.

81557675518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19104.

The product of its digits is 11760000, while the sum is 58.

The spelling of 81557675518 in words is "eighty-one billion, five hundred fifty-seven million, six hundred seventy-five thousand, five hundred eighteen".