20475839 has 2 divisors, whose sum is σ = 20475840. Its totient is φ = 20475838.

The previous prime is 20475817. The next prime is 20475853. The reversal of 20475839 is 93857402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20475839 - 2⁸ = 20475583 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20475859) 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, 10237919 + 10237920.

It is an arithmetic number, because the mean of its divisors is an integer number (10237920).

Almost surely, 2^20475839 is an apocalyptic number.

20475839 is a deficient number, since it is larger than the sum of its proper divisors (1).

20475839 is an equidigital number, since it uses as much as digits as its factorization.

20475839 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 20475839 is about 4525.0236463471. The cubic root of 20475839 is about 273.5776210208.

The spelling of 20475839 in words is "twenty million, four hundred seventy-five thousand, eight hundred thirty-nine".