19938255678 has 64 divisors (see below), whose sum is σ = 49894410240. Its totient is φ = 5846990400.

The previous prime is 19938255677. The next prime is 19938255691. The reversal of 19938255678 is 87655283991.

19938255678 is a `hidden beast` number, since 1 + 9 + 9 + 3 + 8 + 2 + 556 + 78 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19938255671) 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 31 ways as a sum of consecutive naturals, for example, 522975 + ... + 559802.

It is an arithmetic number, because the mean of its divisors is an integer number (779600160).

Almost surely, 2^19938255678 is an apocalyptic number.

19938255678 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

19938255678 is an abundant number, since it is smaller than the sum of its proper divisors (29956154562).

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

19938255678 is a wasteful number, since it uses less digits than its factorization.

19938255678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1082830 (or 1082824 counting only the distinct ones).

The product of its digits is 32659200, while the sum is 63.

The spelling of 19938255678 in words is "nineteen billion, nine hundred thirty-eight million, two hundred fifty-five thousand, six hundred seventy-eight".