20438387 has 2 divisors, whose sum is σ = 20438388. Its totient is φ = 20438386.

The previous prime is 20438371. The next prime is 20438389. The reversal of 20438387 is 78383402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20438387 - 2⁴ = 20438371 is a prime.

Together with 20438389, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20438389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10219193 + 10219194.

It is an arithmetic number, because the mean of its divisors is an integer number (10219194).

Almost surely, 2^20438387 is an apocalyptic number.

20438387 is a deficient number, since it is larger than the sum of its proper divisors (1).

20438387 is an equidigital number, since it uses as much as digits as its factorization.

20438387 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 35.

The square root of 20438387 is about 4520.8834313660. The cubic root of 20438387 is about 273.4107205360.

The spelling of 20438387 in words is "twenty million, four hundred thirty-eight thousand, three hundred eighty-seven".