20005919 has 2 divisors, whose sum is σ = 20005920. Its totient is φ = 20005918.

The previous prime is 20005907. The next prime is 20005949. The reversal of 20005919 is 91950002.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20005919 - 2⁴ = 20005903 is a prime.

It is a super-2 number, since 2×20005919² = 800473590069122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20005949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10002959 + 10002960.

It is an arithmetic number, because the mean of its divisors is an integer number (10002960).

Almost surely, 2^20005919 is an apocalyptic number.

20005919 is a deficient number, since it is larger than the sum of its proper divisors (1).

20005919 is an equidigital number, since it uses as much as digits as its factorization.

20005919 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 810, while the sum is 26.

The square root of 20005919 is about 4472.7976703625. The cubic root of 20005919 is about 271.4685367481.

The spelling of 20005919 in words is "twenty million, five thousand, nine hundred nineteen".