20138320 has 40 divisors (see below), whose sum is σ = 47184480. Its totient is φ = 7992960.

The previous prime is 20138311. The next prime is 20138329. The reversal of 20138320 is 2383102.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20138311) and next prime (20138329).

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20138329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10215 + ... + 12025.

It is an arithmetic number, because the mean of its divisors is an integer number (1179612).

Almost surely, 2^20138320 is an apocalyptic number.

20138320 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 20138320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23592240).

20138320 is an abundant number, since it is smaller than the sum of its proper divisors (27046160).

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

20138320 is a wasteful number, since it uses less digits than its factorization.

20138320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1963 (or 1957 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 20138320 is about 4487.5739548224. The cubic root of 20138320 is about 272.0660883240.

The spelling of 20138320 in words is "twenty million, one hundred thirty-eight thousand, three hundred twenty".