19019840 has 84 divisors (see below), whose sum is σ = 52728876. Its totient is φ = 6515712.

The previous prime is 19019839. The next prime is 19019849. The reversal of 19019840 is 4891091.

It can be written as a sum of positive squares in 2 ways, for example, as 3211264 + 15808576 = 1792^2 + 3976^2 .

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 = 19019797 and 19019806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19019849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15074 + ... + 16286.

Almost surely, 2^19019840 is an apocalyptic number.

19019840 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 19019840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26364438).

19019840 is an abundant number, since it is smaller than the sum of its proper divisors (33709036).

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

19019840 is a wasteful number, since it uses less digits than its factorization.

19019840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1244 (or 1227 counting only the distinct ones).

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

The square root of 19019840 is about 4361.1741538260. The cubic root of 19019840 is about 266.9330116655.

The spelling of 19019840 in words is "nineteen million, nineteen thousand, eight hundred forty".