1649899 has 4 divisors (see below), whose sum is σ = 1654240. Its totient is φ = 1645560.

The previous prime is 1649887. The next prime is 1649917. The reversal of 1649899 is 9989461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9989461 = 2417 ⋅4133.

It is a cyclic number.

It is not a de Polignac number, because 1649899 - 2⁷ = 1649771 is a prime.

It is a Duffinian number.

1649899 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1649819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1539 + ... + 2380.

It is an arithmetic number, because the mean of its divisors is an integer number (413560).

2^1649899 is an apocalyptic number.

1649899 is a deficient number, since it is larger than the sum of its proper divisors (4341).

1649899 is an equidigital number, since it uses as much as digits as its factorization.

1649899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4340.

The product of its digits is 139968, while the sum is 46.

The square root of 1649899 is about 1284.4839430682. The cubic root of 1649899 is about 118.1641639220.

The spelling of 1649899 in words is "one million, six hundred forty-nine thousand, eight hundred ninety-nine".