63561654661 has 4 divisors (see below), whose sum is σ = 63573932800. Its totient is φ = 63549376524.

The previous prime is 63561654631. The next prime is 63561654691. The reversal of 63561654661 is 16645616536.

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 an interprime number because it is at equal distance from previous prime (63561654631) and next prime (63561654691).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-63561654661 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 (63561654601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6131301 + ... + 6141658.

It is an arithmetic number, because the mean of its divisors is an integer number (15893483200).

Almost surely, 2^63561654661 is an apocalyptic number.

It is an amenable number.

63561654661 is a deficient number, since it is larger than the sum of its proper divisors (12278139).

63561654661 is a wasteful number, since it uses less digits than its factorization.

63561654661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12278138.

The product of its digits is 2332800, while the sum is 49.

The spelling of 63561654661 in words is "sixty-three billion, five hundred sixty-one million, six hundred fifty-four thousand, six hundred sixty-one".