20138560 has 112 divisors (see below), whose sum is σ = 53254656. Its totient is φ = 7206912.

The previous prime is 20138533. The next prime is 20138567. The reversal of 20138560 is 6583102.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20138567) 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, 195469 + ... + 195571.

It is an arithmetic number, because the mean of its divisors is an integer number (475488).

Almost surely, 2^20138560 is an apocalyptic number.

20138560 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 20138560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26627328).

20138560 is an abundant number, since it is smaller than the sum of its proper divisors (33116096).

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

20138560 is a wasteful number, since it uses less digits than its factorization.

20138560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180 (or 170 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 20138560 is about 4487.6006952491. The cubic root of 20138560 is about 272.0671691094.

The spelling of 20138560 in words is "twenty million, one hundred thirty-eight thousand, five hundred sixty".