1019855 has 4 divisors (see below), whose sum is σ = 1223832. Its totient is φ = 815880.

The previous prime is 1019849. The next prime is 1019857. The reversal of 1019855 is 5589101.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5589101 = 7 ⋅798443.

It is not a de Polignac number, because 1019855 - 2⁴ = 1019839 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1019857) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 101981 + ... + 101990.

It is an arithmetic number, because the mean of its divisors is an integer number (305958).

2^1019855 is an apocalyptic number.

1019855 is a deficient number, since it is larger than the sum of its proper divisors (203977).

1019855 is an equidigital number, since it uses as much as digits as its factorization.

1019855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203976.

The product of its (nonzero) digits is 1800, while the sum is 29.

The square root of 1019855 is about 1009.8787055880. The cubic root of 1019855 is about 100.6575007858.

The spelling of 1019855 in words is "one million, nineteen thousand, eight hundred fifty-five".