20650139 has 2 divisors, whose sum is σ = 20650140. Its totient is φ = 20650138.

The previous prime is 20650129. The next prime is 20650141. The reversal of 20650139 is 93105602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20650139 - 2²⁰ = 19601563 is a prime.

It is a super-3 number, since 3×20650139³ (a number of 23 digits) contains 333 as substring.

It is a Sophie Germain prime.

Together with 20650141, 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 (20650129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10325069 + 10325070.

It is an arithmetic number, because the mean of its divisors is an integer number (10325070).

Almost surely, 2^20650139 is an apocalyptic number.

20650139 is a deficient number, since it is larger than the sum of its proper divisors (1).

20650139 is an equidigital number, since it uses as much as digits as its factorization.

20650139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1620, while the sum is 26.

The square root of 20650139 is about 4544.2424011049. The cubic root of 20650139 is about 274.3517026277.

The spelling of 20650139 in words is "twenty million, six hundred fifty thousand, one hundred thirty-nine".