1800961 has 2 divisors, whose sum is σ = 1800962. Its totient is φ = 1800960.

The previous prime is 1800959. The next prime is 1800973. The reversal of 1800961 is 1690081.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1640961 + 160000 = 1281^2 + 400^2 .

It is an emirp because it is prime and its reverse (1690081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1800961 - 2¹ = 1800959 is a prime.

Together with 1800959, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1800361) 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, 900480 + 900481.

It is an arithmetic number, because the mean of its divisors is an integer number (900481).

2^1800961 is an apocalyptic number.

It is an amenable number.

1800961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1800961 is an equidigital number, since it uses as much as digits as its factorization.

1800961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 1800961 is about 1341.9988822648. The cubic root of 1800961 is about 121.6656841938.

The spelling of 1800961 in words is "one million, eight hundred thousand, nine hundred sixty-one".