19784840238 has 12 divisors (see below), whose sum is σ = 42867153888. Its totient is φ = 6594946740.

The previous prime is 19784840233. The next prime is 19784840263. The reversal of 19784840238 is 83204848791.

It is a happy number.

19784840238 is a `hidden beast` number, since 197 + 8 + 48 + 402 + 3 + 8 = 666.

It is a super-3 number, since 3×19784840238³ (a number of 32 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19784840233) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 549578878 + ... + 549578913.

It is an arithmetic number, because the mean of its divisors is an integer number (3572262824).

Almost surely, 2^19784840238 is an apocalyptic number.

19784840238 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

19784840238 is an abundant number, since it is smaller than the sum of its proper divisors (23082313650).

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

19784840238 is a wasteful number, since it uses less digits than its factorization.

19784840238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1099157799 (or 1099157796 counting only the distinct ones).

The product of its (nonzero) digits is 3096576, while the sum is 54.

The spelling of 19784840238 in words is "nineteen billion, seven hundred eighty-four million, eight hundred forty thousand, two hundred thirty-eight".