19978056 has 128 divisors (see below), whose sum is σ = 64646400. Its totient is φ = 5598720.

The previous prime is 19978037. The next prime is 19978067. The reversal of 19978056 is 65087991.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 110286 + ... + 110466.

It is an arithmetic number, because the mean of its divisors is an integer number (505050).

Almost surely, 2^19978056 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19978056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32323200).

19978056 is an abundant number, since it is smaller than the sum of its proper divisors (44668344).

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

19978056 is a wasteful number, since it uses less digits than its factorization.

19978056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276 (or 266 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 45.

The square root of 19978056 is about 4469.6818678738. The cubic root of 19978056 is about 271.3424500288.

The spelling of 19978056 in words is "nineteen million, nine hundred seventy-eight thousand, fifty-six".