18199512408 has 128 divisors (see below), whose sum is σ = 57687552000. Its totient is φ = 4646997120.

The previous prime is 18199512403. The next prime is 18199512413. The reversal of 18199512408 is 80421599181.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18199512403) and next prime (18199512413).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18199512403) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25573 + ... + 192491.

It is an arithmetic number, because the mean of its divisors is an integer number (450684000).

Almost surely, 2^18199512408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18199512408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28843776000).

18199512408 is an abundant number, since it is smaller than the sum of its proper divisors (39488039592).

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

18199512408 is a wasteful number, since it uses less digits than its factorization.

18199512408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167005 (or 167001 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 48.

The spelling of 18199512408 in words is "eighteen billion, one hundred ninety-nine million, five hundred twelve thousand, four hundred eight".