19864810101800 has 48 divisors (see below), whose sum is σ = 46194162013500. Its totient is φ = 7944465369600.

The previous prime is 19864810101797. The next prime is 19864810101803. The reversal of 19864810101800 is 810101846891.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (19864810101797) and next prime (19864810101803).

It can be written as a sum of positive squares in 6 ways, for example, as 266357145604 + 19598452956196 = 516098^2 + 4427014^2 .

It is a super-2 number, since 2×19864810101800² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19864810101803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8024171 + ... + 10203770.

Almost surely, 2^{19864810101800} is an apocalyptic number.

19864810101800 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19864810101800 is an abundant number, since it is smaller than the sum of its proper divisors (26329351911700).

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

19864810101800 is a wasteful number, since it uses less digits than its factorization.

19864810101800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18233406 (or 18233397 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 47.

The spelling of 19864810101800 in words is "nineteen trillion, eight hundred sixty-four billion, eight hundred ten million, one hundred one thousand, eight hundred".