1649897 has 4 divisors (see below), whose sum is σ = 1706820. Its totient is φ = 1592976.

The previous prime is 1649887. The next prime is 1649917. The reversal of 1649897 is 7989461.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 524176 + 1125721 = 724^2 + 1061^2 .

It is a cyclic number.

It is not a de Polignac number, because 1649897 - 2¹² = 1645801 is a prime.

It is a super-2 number, since 2×1649897² = 5444320221218, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1649807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28418 + ... + 28475.

It is an arithmetic number, because the mean of its divisors is an integer number (426705).

2^1649897 is an apocalyptic number.

It is an amenable number.

1649897 is a deficient number, since it is larger than the sum of its proper divisors (56923).

1649897 is an equidigital number, since it uses as much as digits as its factorization.

1649897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56922.

The product of its digits is 108864, while the sum is 44.

The square root of 1649897 is about 1284.4831645452. The cubic root of 1649897 is about 118.1641161759.

The spelling of 1649897 in words is "one million, six hundred forty-nine thousand, eight hundred ninety-seven".