1909231 has 2 divisors, whose sum is σ = 1909232. Its totient is φ = 1909230.

The previous prime is 1909223. The next prime is 1909241. The reversal of 1909231 is 1329091.

It is a weak prime.

It is an emirp because it is prime and its reverse (1329091) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1909231 - 2³ = 1909223 is a prime.

It is a super-2 number, since 2×1909231² = 7290326022722, which contains 22 as substring.

1909231 is a lucky number.

It is equal to p₁₄₂₆₆₆ and since 1909231 and 142666 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 1909196 and 1909205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1909241) 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, 954615 + 954616.

It is an arithmetic number, because the mean of its divisors is an integer number (954616).

2^1909231 is an apocalyptic number.

1909231 is a deficient number, since it is larger than the sum of its proper divisors (1).

1909231 is an equidigital number, since it uses as much as digits as its factorization.

1909231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 486, while the sum is 25.

The square root of 1909231 is about 1381.7492536636. The cubic root of 1909231 is about 124.0564909097.

The spelling of 1909231 in words is "one million, nine hundred nine thousand, two hundred thirty-one".