21121979233 has 2 divisors, whose sum is σ = 21121979234. Its totient is φ = 21121979232.

The previous prime is 21121979189. The next prime is 21121979243. The reversal of 21121979233 is 33297912112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20501371489 + 620607744 = 143183^2 + 24912^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121979233 - 2²⁹ = 20585108321 is a prime.

It is a super-3 number, since 3×21121979233³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (21121979243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560989616 + 10560989617.

It is an arithmetic number, because the mean of its divisors is an integer number (10560989617).

Almost surely, 2^21121979233 is an apocalyptic number.

It is an amenable number.

21121979233 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121979233 is an equidigital number, since it uses as much as digits as its factorization.

21121979233 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 40.

The spelling of 21121979233 in words is "twenty-one billion, one hundred twenty-one million, nine hundred seventy-nine thousand, two hundred thirty-three".