20138389 has 2 divisors, whose sum is σ = 20138390. Its totient is φ = 20138388.

The previous prime is 20138351. The next prime is 20138407. The reversal of 20138389 is 98383102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17918289 + 2220100 = 4233^2 + 1490^2 .

It is a cyclic number.

It is not a de Polignac number, because 20138389 - 2¹³ = 20130197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20138329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10069194 + 10069195.

It is an arithmetic number, because the mean of its divisors is an integer number (10069195).

Almost surely, 2^20138389 is an apocalyptic number.

It is an amenable number.

20138389 is a deficient number, since it is larger than the sum of its proper divisors (1).

20138389 is an equidigital number, since it uses as much as digits as its factorization.

20138389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 20138389 is about 4487.5816427114. The cubic root of 20138389 is about 272.0663990507.

The spelling of 20138389 in words is "twenty million, one hundred thirty-eight thousand, three hundred eighty-nine".