19808856 has 96 divisors (see below), whose sum is σ = 56862000. Its totient is φ = 6220032.

The previous prime is 19808839. The next prime is 19808861. The reversal of 19808856 is 65880891.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 110575 + ... + 110753.

Almost surely, 2^19808856 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 19808856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28431000).

19808856 is an abundant number, since it is smaller than the sum of its proper divisors (37053144).

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

19808856 is a wasteful number, since it uses less digits than its factorization.

19808856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273 (or 266 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 45.

The square root of 19808856 is about 4450.7141000069. The cubic root of 19808856 is about 270.5742510361.

It can be divided in two parts, 1980885 and 6, that added together give a palindrome (1980891).

The spelling of 19808856 in words is "nineteen million, eight hundred eight thousand, eight hundred fifty-six".