20046656661 has 4 divisors (see below), whose sum is σ = 26728875552. Its totient is φ = 13364437772.

The previous prime is 20046656639. The next prime is 20046656681. The reversal of 20046656661 is 16665664002.

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 not a de Polignac number, because 20046656661 - 2¹⁴ = 20046640277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20046656621) 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, 3341109441 + ... + 3341109446.

It is an arithmetic number, because the mean of its divisors is an integer number (6682218888).

Almost surely, 2^20046656661 is an apocalyptic number.

It is an amenable number.

20046656661 is a deficient number, since it is larger than the sum of its proper divisors (6682218891).

20046656661 is an equidigital number, since it uses as much as digits as its factorization.

20046656661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6682218890.

The product of its (nonzero) digits is 311040, while the sum is 42.

The spelling of 20046656661 in words is "twenty billion, forty-six million, six hundred fifty-six thousand, six hundred sixty-one".