2668445649 has 27 divisors (see below), whose sum is σ = 3928092987. Its totient is φ = 1745593344.

The previous prime is 2668445627. The next prime is 2668445657. The reversal of 2668445649 is 9465448662.

The square root of 2668445649 is 51657.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 2627075025 + 41370624 = 51255^2 + 6432^2 .

It is not a de Polignac number, because 2668445649 - 2²¹ = 2666348497 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2668445595 and 2668445604.

It is not an unprimeable number, because it can be changed into a prime (2668445449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 10382929 + ... + 10383185.

Almost surely, 2^2668445649 is an apocalyptic number.

2668445649 is the 51657-th square number.

2668445649 is the 25829-th centered octagonal number.

It is an amenable number.

2668445649 is a deficient number, since it is larger than the sum of its proper divisors (1259647338).

2668445649 is an frugal number, since it uses more digits than its factorization.

2668445649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654 (or 327 counting only the distinct ones).

The product of its digits is 9953280, while the sum is 54.

The cubic root of 2668445649 is about 1387.0308495181.

The spelling of 2668445649 in words is "two billion, six hundred sixty-eight million, four hundred forty-five thousand, six hundred forty-nine".