21183949211 has 2 divisors, whose sum is σ = 21183949212. Its totient is φ = 21183949210.

The previous prime is 21183949207. The next prime is 21183949223. The reversal of 21183949211 is 11294938112.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21183949211 - 2² = 21183949207 is a prime.

It is not a weakly prime, because it can be changed into another prime (21183949511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10591974605 + 10591974606.

It is an arithmetic number, because the mean of its divisors is an integer number (10591974606).

Almost surely, 2^21183949211 is an apocalyptic number.

21183949211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21183949211 is an equidigital number, since it uses as much as digits as its factorization.

21183949211 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 41.

The spelling of 21183949211 in words is "twenty-one billion, one hundred eighty-three million, nine hundred forty-nine thousand, two hundred eleven".