1820549 has 2 divisors, whose sum is σ = 1820550. Its totient is φ = 1820548.

The previous prime is 1820527. The next prime is 1820551. The reversal of 1820549 is 9450281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1803649 + 16900 = 1343^2 + 130^2 .

It is a cyclic number.

It is not a de Polignac number, because 1820549 - 2⁸ = 1820293 is a prime.

It is a super-2 number, since 2×1820549² = 6628797322802, which contains 22 as substring.

Together with 1820551, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1820509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910274 + 910275.

It is an arithmetic number, because the mean of its divisors is an integer number (910275).

2^1820549 is an apocalyptic number.

It is an amenable number.

1820549 is a deficient number, since it is larger than the sum of its proper divisors (1).

1820549 is an equidigital number, since it uses as much as digits as its factorization.

1820549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 1820549 is about 1349.2772139186. The cubic root of 1820549 is about 122.1051901160.

The spelling of 1820549 in words is "one million, eight hundred twenty thousand, five hundred forty-nine".