2643620849 has 4 divisors (see below), whose sum is σ = 2652067236. Its totient is φ = 2635174464.

The previous prime is 2643620839. The next prime is 2643620857. The reversal of 2643620849 is 9480263462.

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 52301824 + 2591319025 = 7232^2 + 50905^2 .

It is a cyclic number.

It is not a de Polignac number, because 2643620849 - 2⁸ = 2643620593 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2643620839) 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, 4222724 + ... + 4223349.

It is an arithmetic number, because the mean of its divisors is an integer number (663016809).

Almost surely, 2^2643620849 is an apocalyptic number.

It is an amenable number.

2643620849 is a deficient number, since it is larger than the sum of its proper divisors (8446387).

2643620849 is an equidigital number, since it uses as much as digits as its factorization.

2643620849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8446386.

The product of its (nonzero) digits is 497664, while the sum is 44.

The square root of 2643620849 is about 51416.1535803681. The cubic root of 2643620849 is about 1382.7162159120.

The spelling of 2643620849 in words is "two billion, six hundred forty-three million, six hundred twenty thousand, eight hundred forty-nine".