1649889 has 10 divisors (see below), whose sum is σ = 2464770. Its totient is φ = 1099872.

The previous prime is 1649887. The next prime is 1649917. The reversal of 1649889 is 9889461.

It can be written as a sum of positive squares in only one way, i.e., 1520289 + 129600 = 1233^2 + 360^2 .

It is not a de Polignac number, because 1649889 - 2¹ = 1649887 is a prime.

1649889 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1649887) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 10104 + ... + 10265.

It is an arithmetic number, because the mean of its divisors is an integer number (246477).

2^1649889 is an apocalyptic number.

It is an amenable number.

1649889 is a deficient number, since it is larger than the sum of its proper divisors (814881).

1649889 is an equidigital number, since it uses as much as digits as its factorization.

1649889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20381 (or 20372 counting only the distinct ones).

The product of its digits is 124416, while the sum is 45.

The square root of 1649889 is about 1284.4800504484. The cubic root of 1649889 is about 118.1639251914.

The spelling of 1649889 in words is "one million, six hundred forty-nine thousand, eight hundred eighty-nine".