19864185855 has 32 divisors (see below), whose sum is σ = 32236389120. Its totient is φ = 10443168000.

The previous prime is 19864185853. The next prime is 19864185863. The reversal of 19864185855 is 55858146891.

It is not a de Polignac number, because 19864185855 - 2¹ = 19864185853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19864185853) 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, 2460816 + ... + 2468874.

It is an arithmetic number, because the mean of its divisors is an integer number (1007387160).

Almost surely, 2^19864185855 is an apocalyptic number.

19864185855 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

19864185855 is a deficient number, since it is larger than the sum of its proper divisors (12372203265).

19864185855 is a wasteful number, since it uses less digits than its factorization.

19864185855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10391.

The product of its digits is 13824000, while the sum is 60.

The spelling of 19864185855 in words is "nineteen billion, eight hundred sixty-four million, one hundred eighty-five thousand, eight hundred fifty-five".