19819040 has 48 divisors (see below), whose sum is σ = 47342232. Its totient is φ = 7839744.

The previous prime is 19819039. The next prime is 19819057. The reversal of 19819040 is 4091891.

It can be written as a sum of positive squares in 4 ways, for example, as 16679056 + 3139984 = 4084^2 + 1772^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 19818988 and 19819006.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14882 + ... + 16158.

Almost surely, 2^19819040 is an apocalyptic number.

19819040 is a gapful number since it is divisible by the number (10) 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 19819040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23671116).

19819040 is an abundant number, since it is smaller than the sum of its proper divisors (27523192).

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

19819040 is a wasteful number, since it uses less digits than its factorization.

19819040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1389 (or 1381 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 19819040 is about 4451.8580390664. The cubic root of 19819040 is about 270.6206117158.

The spelling of 19819040 in words is "nineteen million, eight hundred nineteen thousand, forty".