20920320 has 144 divisors (see below), whose sum is σ = 72825480. Its totient is φ = 5554176.

The previous prime is 20920313. The next prime is 20920321. The reversal of 20920320 is 2302902.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20920293 and 20920302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20920321) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 92047 + ... + 92273.

Almost surely, 2^20920320 is an apocalyptic number.

20920320 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 20920320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36412740).

20920320 is an abundant number, since it is smaller than the sum of its proper divisors (51905160).

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

20920320 is a wasteful number, since it uses less digits than its factorization.

20920320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260 (or 237 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 20920320 is about 4573.8736318355. The cubic root of 20920320 is about 275.5430371621.

The spelling of 20920320 in words is "twenty million, nine hundred twenty thousand, three hundred twenty".