20266606661 has 16 divisors (see below), whose sum is σ = 24544396800. Its totient is φ = 16336131840.

The previous prime is 20266606643. The next prime is 20266606669. The reversal of 20266606661 is 16660666202.

It is not a de Polignac number, because 20266606661 - 2⁶ = 20266606597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20266606669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77315 + ... + 215663.

It is an arithmetic number, because the mean of its divisors is an integer number (1534024800).

Almost surely, 2^20266606661 is an apocalyptic number.

It is an amenable number.

20266606661 is a deficient number, since it is larger than the sum of its proper divisors (4277790139).

20266606661 is a wasteful number, since it uses less digits than its factorization.

20266606661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139604.

The product of its (nonzero) digits is 186624, while the sum is 41.

The spelling of 20266606661 in words is "twenty billion, two hundred sixty-six million, six hundred six thousand, six hundred sixty-one".