90019 has 2 divisors, whose sum is σ = 90020. Its totient is φ = 90018.

The previous prime is 90017. The next prime is 90023. The reversal of 90019 is 91009.

It is a weak prime.

It is an emirp because it is prime and its reverse (91009) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90019 - 2¹ = 90017 is a prime.

It is a super-2 number, since 2×90019² = 16206840722, which contains 22 as substring.

Together with 90017, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 89978 and 90005.

It is not a weakly prime, because it can be changed into another prime (90011) 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, 45009 + 45010.

It is an arithmetic number, because the mean of its divisors is an integer number (45010).

2⁹⁰⁰¹⁹ is an apocalyptic number.

90019 is a deficient number, since it is larger than the sum of its proper divisors (1).

90019 is an equidigital number, since it uses as much as digits as its factorization.

90019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81, while the sum is 19.

The square root of 90019 is about 300.0316649955. The cubic root of 90019 is about 44.8172008248.

Subtracting from 90019 its sum of digits (19), we obtain a square (90000 = 300²).

Adding to 90019 its product of nonzero digits (81), we get a triangular number (90100 = T₄₂₄).

Subtracting 90019 from its reverse (91009), we obtain a triangular number (990 = T₄₄).

It can be divided in two parts, 900 and 19, that added together give a palindrome (919).

The spelling of 90019 in words is "ninety thousand, nineteen".