1649689 has 2 divisors, whose sum is σ = 1649690. Its totient is φ = 1649688.

The previous prime is 1649677. The next prime is 1649693. The reversal of 1649689 is 9869461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1646089 + 3600 = 1283^2 + 60^2 .

It is a cyclic number.

It is not a de Polignac number, because 1649689 - 2⁵ = 1649657 is a prime.

It is not a weakly prime, because it can be changed into another prime (1649639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 824844 + 824845.

It is an arithmetic number, because the mean of its divisors is an integer number (824845).

2^1649689 is an apocalyptic number.

It is an amenable number.

1649689 is a deficient number, since it is larger than the sum of its proper divisors (1).

1649689 is an equidigital number, since it uses as much as digits as its factorization.

1649689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 43.

The square root of 1649689 is about 1284.4021955758. The cubic root of 1649689 is about 118.1591503773.

The spelling of 1649689 in words is "one million, six hundred forty-nine thousand, six hundred eighty-nine".