81115109619 has 8 divisors (see below), whose sum is σ = 108258385152. Its totient is φ = 54024286920.

The previous prime is 81115109611. The next prime is 81115109627. The reversal of 81115109619 is 91690151118.

It is an interprime number because it is at equal distance from previous prime (81115109611) and next prime (81115109627).

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

It is not a de Polignac number, because 81115109619 - 2³ = 81115109611 is a prime.

It is a super-2 number, since 2×81115109619² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81115109611) 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, 13109599 + ... + 13115784.

It is an arithmetic number, because the mean of its divisors is an integer number (13532298144).

Almost surely, 2^81115109619 is an apocalyptic number.

81115109619 is a deficient number, since it is larger than the sum of its proper divisors (27143275533).

81115109619 is a wasteful number, since it uses less digits than its factorization.

81115109619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26226417.

The product of its (nonzero) digits is 19440, while the sum is 42.

The spelling of 81115109619 in words is "eighty-one billion, one hundred fifteen million, one hundred nine thousand, six hundred nineteen".