20665365266 has 128 divisors (see below), whose sum is σ = 41388834816. Its totient is φ = 7513482240.

The previous prime is 20665365247. The next prime is 20665365271. The reversal of 20665365266 is 66256356602.

It is a self number, because there is not a number n which added to its sum of digits gives 20665365266.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21151370 + ... + 21152346.

It is an arithmetic number, because the mean of its divisors is an integer number (323350272).

Almost surely, 2^20665365266 is an apocalyptic number.

20665365266 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

20665365266 is an abundant number, since it is smaller than the sum of its proper divisors (20723469550).

20665365266 is a wasteful number, since it uses less digits than its factorization.

20665365266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1216.

The product of its (nonzero) digits is 2332800, while the sum is 47.

The spelling of 20665365266 in words is "twenty billion, six hundred sixty-five million, three hundred sixty-five thousand, two hundred sixty-six".