18219639798 has 16 divisors (see below), whose sum is σ = 40488088560. Its totient is φ = 6073213248.

The previous prime is 18219639793. The next prime is 18219639829. The reversal of 18219639798 is 89793691281.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18219639791) 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, 168700315 + ... + 168700422.

It is an arithmetic number, because the mean of its divisors is an integer number (2530505535).

Almost surely, 2^18219639798 is an apocalyptic number.

18219639798 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18219639798 is an abundant number, since it is smaller than the sum of its proper divisors (22268448762).

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

18219639798 is a wasteful number, since it uses less digits than its factorization.

18219639798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337400748 (or 337400742 counting only the distinct ones).

The product of its digits is 11757312, while the sum is 63.

The spelling of 18219639798 in words is "eighteen billion, two hundred nineteen million, six hundred thirty-nine thousand, seven hundred ninety-eight".