20123280 has 120 divisors (see below), whose sum is σ = 71185920. Its totient is φ = 5080320.

The previous prime is 20123273. The next prime is 20123287. The reversal of 20123280 is 8232102.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20123273) and next prime (20123287).

It is a tau number, because it is divible by the number of its divisors (120).

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

It is not an unprimeable number, because it can be changed into a prime (20123287) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12945 + ... + 14415.

It is an arithmetic number, because the mean of its divisors is an integer number (593216).

Almost surely, 2^20123280 is an apocalyptic number.

20123280 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 20123280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35592960).

20123280 is an abundant number, since it is smaller than the sum of its proper divisors (51062640).

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

20123280 is a wasteful number, since it uses less digits than its factorization.

20123280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1509 (or 1500 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 20123280 is about 4485.8979034303. The cubic root of 20123280 is about 271.9983419737.

Adding to 20123280 its reverse (8232102), we get a palindrome (28355382).

The spelling of 20123280 in words is "twenty million, one hundred twenty-three thousand, two hundred eighty".