1801309 has 2 divisors, whose sum is σ = 1801310. Its totient is φ = 1801308.

The previous prime is 1801297. The next prime is 1801339. The reversal of 1801309 is 9031081.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1493284 + 308025 = 1222^2 + 555^2 .

It is a cyclic number.

It is not a de Polignac number, because 1801309 - 2¹¹ = 1799261 is a prime.

It is a super-2 number, since 2×1801309² = 6489428226962, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1801309.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1801339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 900654 + 900655.

It is an arithmetic number, because the mean of its divisors is an integer number (900655).

2^1801309 is an apocalyptic number.

It is an amenable number.

1801309 is a deficient number, since it is larger than the sum of its proper divisors (1).

1801309 is an equidigital number, since it uses as much as digits as its factorization.

1801309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 1801309 is about 1342.1285333380. The cubic root of 1801309 is about 121.6735201827.

The spelling of 1801309 in words is "one million, eight hundred one thousand, three hundred nine".