1891249 has 2 divisors, whose sum is σ = 1891250. Its totient is φ = 1891248.

The previous prime is 1891243. The next prime is 1891273. The reversal of 1891249 is 9421981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1199025 + 692224 = 1095^2 + 832^2 .

It is an emirp because it is prime and its reverse (9421981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1891249 - 2¹¹ = 1889201 is a prime.

It is a super-3 number, since 3×1891249³ = 20293987517562333747, which contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (1891243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 945624 + 945625.

It is an arithmetic number, because the mean of its divisors is an integer number (945625).

2^1891249 is an apocalyptic number.

It is an amenable number.

1891249 is a deficient number, since it is larger than the sum of its proper divisors (1).

1891249 is an equidigital number, since it uses as much as digits as its factorization.

1891249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 34.

The square root of 1891249 is about 1375.2268903712. The cubic root of 1891249 is about 123.6657883692.

The spelling of 1891249 in words is "one million, eight hundred ninety-one thousand, two hundred forty-nine".