19801056 has 96 divisors (see below), whose sum is σ = 60092928. Its totient is φ = 5642240.

The previous prime is 19801051. The next prime is 19801069. The reversal of 19801056 is 65010891.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19801051) 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 15 ways as a sum of consecutive naturals, for example, 17401 + ... + 18503.

It is an arithmetic number, because the mean of its divisors is an integer number (625968).

Almost surely, 2^19801056 is an apocalyptic number.

19801056 is a gapful number since it is divisible by the number (16) 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 19801056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30046464).

19801056 is an abundant number, since it is smaller than the sum of its proper divisors (40291872).

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

19801056 is a wasteful number, since it uses less digits than its factorization.

19801056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1144 (or 1136 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 30.

The square root of 19801056 is about 4449.8377498511. The cubic root of 19801056 is about 270.5387323060.

The spelling of 19801056 in words is "nineteen million, eight hundred one thousand, fifty-six".