1683949649 has 4 divisors (see below), whose sum is σ = 1693683636. Its totient is φ = 1674215664.

The previous prime is 1683949639. The next prime is 1683949679. The reversal of 1683949649 is 9469493861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9469493861 = 6451 ⋅1467911.

It can be written as a sum of positive squares in 2 ways, for example, as 1106028049 + 577921600 = 33257^2 + 24040^2 .

It is a cyclic number.

It is not a de Polignac number, because 1683949649 - 2⁴ = 1683949633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1683949639) 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 in 3 ways as a sum of consecutive naturals, for example, 4866734 + ... + 4867079.

It is an arithmetic number, because the mean of its divisors is an integer number (423420909).

Almost surely, 2^1683949649 is an apocalyptic number.

It is an amenable number.

1683949649 is a deficient number, since it is larger than the sum of its proper divisors (9733987).

1683949649 is an equidigital number, since it uses as much as digits as its factorization.

1683949649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9733986.

The product of its digits is 10077696, while the sum is 59.

The square root of 1683949649 is about 41035.9555633837. The cubic root of 1683949649 is about 1189.7152648326.

It can be divided in two parts, 1683949 and 649, that multiplied together give a palindrome (1092882901).

The spelling of 1683949649 in words is "one billion, six hundred eighty-three million, nine hundred forty-nine thousand, six hundred forty-nine".