19896840 has 192 divisors, whose sum is σ = 70761600. Its totient is φ = 5018112.

The previous prime is 19896809. The next prime is 19896841. The reversal of 19896840 is 4869891.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (19896841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 223516 + ... + 223604.

It is an arithmetic number, because the mean of its divisors is an integer number (368550).

Almost surely, 2^19896840 is an apocalyptic number.

19896840 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 19896840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35380800).

19896840 is an abundant number, since it is smaller than the sum of its proper divisors (50864760).

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

19896840 is a wasteful number, since it uses less digits than its factorization.

19896840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The square root of 19896840 is about 4460.5874052640. The cubic root of 19896840 is about 270.9742580724.

It can be divided in two parts, 19896 and 840, that added together give a 4-th power (20736 = 12⁴).

The spelling of 19896840 in words is "nineteen million, eight hundred ninety-six thousand, eight hundred forty".