18109628691 has 48 divisors (see below), whose sum is σ = 30958058880. Its totient is φ = 9310533120.

The previous prime is 18109628687. The next prime is 18109628737. The reversal of 18109628691 is 19682690181.

It is not a de Polignac number, because 18109628691 - 2² = 18109628687 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18109628591) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 99120 + ... + 214578.

It is an arithmetic number, because the mean of its divisors is an integer number (644959560).

Almost surely, 2^18109628691 is an apocalyptic number.

18109628691 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

18109628691 is a deficient number, since it is larger than the sum of its proper divisors (12848430189).

18109628691 is a wasteful number, since it uses less digits than its factorization.

18109628691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115584 (or 115577 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 51.

The spelling of 18109628691 in words is "eighteen billion, one hundred nine million, six hundred twenty-eight thousand, six hundred ninety-one".