2665242440561 has 4 divisors (see below), whose sum is σ = 2665263028800. Its totient is φ = 2665221852324.

The previous prime is 2665242440551. The next prime is 2665242440659. The reversal of 2665242440561 is 1650442425662.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2665242440561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2665242440551) 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, 10098701 + ... + 10359258.

It is an arithmetic number, because the mean of its divisors is an integer number (666315757200).

Almost surely, 2^{2665242440561} is an apocalyptic number.

It is an amenable number.

2665242440561 is a deficient number, since it is larger than the sum of its proper divisors (20588239).

2665242440561 is a wasteful number, since it uses less digits than its factorization.

2665242440561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20588238.

The product of its (nonzero) digits is 2764800, while the sum is 47.

The spelling of 2665242440561 in words is "two trillion, six hundred sixty-five billion, two hundred forty-two million, four hundred forty thousand, five hundred sixty-one".