1806869 has 2 divisors, whose sum is σ = 1806870. Its totient is φ = 1806868.

The previous prime is 1806863. The next prime is 1806877. The reversal of 1806869 is 9686081.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1020100 + 786769 = 1010^2 + 887^2 .

It is an emirp because it is prime and its reverse (9686081) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1806869 is a prime.

It is a super-2 number, since 2×1806869² = 6529551166322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1806863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 903434 + 903435.

It is an arithmetic number, because the mean of its divisors is an integer number (903435).

2^1806869 is an apocalyptic number.

It is an amenable number.

1806869 is a deficient number, since it is larger than the sum of its proper divisors (1).

1806869 is an equidigital number, since it uses as much as digits as its factorization.

1806869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 1806869 is about 1344.1982740653. The cubic root of 1806869 is about 121.7985792222.

The spelling of 1806869 in words is "one million, eight hundred six thousand, eight hundred sixty-nine".