21123223266 has 8 divisors (see below), whose sum is σ = 42246446544. Its totient is φ = 7041074420.

The previous prime is 21123223259. The next prime is 21123223273. The reversal of 21123223266 is 66232232112.

It is an interprime number because it is at equal distance from previous prime (21123223259) and next prime (21123223273).

It is a sphenic number, since it is the product of 3 distinct primes.

21123223266 is an admirable number.

It is a super-2 number, since 2×21123223266² (a number of 21 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1760268600 + ... + 1760268611.

It is an arithmetic number, because the mean of its divisors is an integer number (5280805818).

Almost surely, 2^21123223266 is an apocalyptic number.

21123223266 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21123223266 is a wasteful number, since it uses less digits than its factorization.

21123223266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3520537216.

The product of its digits is 10368, while the sum is 30.

Adding to 21123223266 its reverse (66232232112), we get a palindrome (87355455378).

The spelling of 21123223266 in words is "twenty-one billion, one hundred twenty-three million, two hundred twenty-three thousand, two hundred sixty-six".