6666223261 has 2 divisors, whose sum is σ = 6666223262. Its totient is φ = 6666223260.

The previous prime is 6666223259. The next prime is 6666223327. The reversal of 6666223261 is 1623226666.

6666223261 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6520562500 + 145660761 = 80750^2 + 12069^2 .

It is a cyclic number.

It is not a de Polignac number, because 6666223261 - 2¹ = 6666223259 is a prime.

Together with 6666223259, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6666223061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3333111630 + 3333111631.

It is an arithmetic number, because the mean of its divisors is an integer number (3333111631).

Almost surely, 2^6666223261 is an apocalyptic number.

It is an amenable number.

6666223261 is a deficient number, since it is larger than the sum of its proper divisors (1).

6666223261 is an equidigital number, since it uses as much as digits as its factorization.

6666223261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 40.

The square root of 6666223261 is about 81646.9427535410. The cubic root of 6666223261 is about 1882.0303307662.

The spelling of 6666223261 in words is "six billion, six hundred sixty-six million, two hundred twenty-three thousand, two hundred sixty-one".