19781104 has 60 divisors (see below), whose sum is σ = 46563984. Its totient is φ = 8101632.

The previous prime is 19781089. The next prime is 19781119. The reversal of 19781104 is 40118791.

It is an interprime number because it is at equal distance from previous prime (19781089) and next prime (19781119).

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17484 + ... + 18580.

Almost surely, 2^19781104 is an apocalyptic number.

19781104 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19781104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23281992).

19781104 is an abundant number, since it is smaller than the sum of its proper divisors (26782880).

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

19781104 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (19781103) it forms a Ruth-Aaron pair, since the sum of their prime factors is the same (1142).

19781104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1142 (or 1129 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 19781104 is about 4447.5953053307. The cubic root of 19781104 is about 270.4478347501.

Adding to 19781104 its reverse (40118791), we get a palindrome (59899895).

The spelling of 19781104 in words is "nineteen million, seven hundred eighty-one thousand, one hundred four".