2688560991 has 24 divisors (see below), whose sum is σ = 4034102800. Its totient is φ = 1789350912.

The previous prime is 2688560981. The next prime is 2688560993. The reversal of 2688560991 is 1990658862.

It is a happy number.

2688560991 is a `hidden beast` number, since 26 + 8 + 8 + 5 + 609 + 9 + 1 = 666.

It is not a de Polignac number, because 2688560991 - 2¹³ = 2688552799 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2688560993) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 139935 + ... + 157983.

Almost surely, 2^2688560991 is an apocalyptic number.

2688560991 is a deficient number, since it is larger than the sum of its proper divisors (1345541809).

2688560991 is an equidigital number, since it uses as much as digits as its factorization.

2688560991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18677 (or 18665 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 54.

The square root of 2688560991 is about 51851.3354794262. The cubic root of 2688560991 is about 1390.5073783922.

The spelling of 2688560991 in words is "two billion, six hundred eighty-eight million, five hundred sixty thousand, nine hundred ninety-one".