19727840 has 72 divisors (see below), whose sum is σ = 51279480. Its totient is φ = 7166720.

The previous prime is 19727839. The next prime is 19727843. The reversal of 19727840 is 4872791.

It is a junction number, because it is equal to n+sod(n) for n = 19727794 and 19727803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19727843) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18851 + ... + 19869.

It is an arithmetic number, because the mean of its divisors is an integer number (712215).

Almost surely, 2^19727840 is an apocalyptic number.

19727840 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 19727840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25639740).

19727840 is an abundant number, since it is smaller than the sum of its proper divisors (31551640).

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

19727840 is a wasteful number, since it uses less digits than its factorization.

19727840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056 (or 1037 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 19727840 is about 4441.6033141198. The cubic root of 19727840 is about 270.2048742245.

The spelling of 19727840 in words is "nineteen million, seven hundred twenty-seven thousand, eight hundred forty".