20855120 has 80 divisors (see below), whose sum is σ = 56996352. Its totient is φ = 6996480.

The previous prime is 20855117. The next prime is 20855123. The reversal of 20855120 is 2155802.

It is an interprime number because it is at equal distance from previous prime (20855117) and next prime (20855123).

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20855123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10529 + ... + 12351.

Almost surely, 2^20855120 is an apocalyptic number.

20855120 is a gapful number since it is divisible by the number (20) 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 20855120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28498176).

20855120 is an abundant number, since it is smaller than the sum of its proper divisors (36141232).

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

20855120 is a wasteful number, since it uses less digits than its factorization.

20855120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1860 (or 1854 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 20855120 is about 4566.7406320044. The cubic root of 20855120 is about 275.2564879762.

The spelling of 20855120 in words is "twenty million, eight hundred fifty-five thousand, one hundred twenty".