2640413553561 has 18 divisors (see below), whose sum is σ = 4436613250602. Its totient is φ = 1508807744640.

The previous prime is 2640413553541. The next prime is 2640413553577. The reversal of 2640413553561 is 1653553140462.

It is a happy number.

2640413553561 is a `hidden beast` number, since 2 + 6 + 4 + 0 + 4 + 1 + 35 + 53 + 561 = 666.

It can be written as a sum of positive squares in only one way, i.e., 2305936397961 + 334477155600 = 1518531^2 + 578340^2 .

It is not a de Polignac number, because 2640413553561 - 2¹³ = 2640413545369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2640413553541) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2993665720 + ... + 2993666601.

Almost surely, 2^{2640413553561} is an apocalyptic number.

2640413553561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2640413553561 is a deficient number, since it is larger than the sum of its proper divisors (1796199697041).

2640413553561 is a wasteful number, since it uses less digits than its factorization.

2640413553561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5987332341 (or 5987332331 counting only the distinct ones).

The product of its (nonzero) digits is 1296000, while the sum is 45.

The spelling of 2640413553561 in words is "two trillion, six hundred forty billion, four hundred thirteen million, five hundred fifty-three thousand, five hundred sixty-one".