21111373 has 2 divisors, whose sum is σ = 21111374. Its totient is φ = 21111372.

The previous prime is 21111301. The next prime is 21111383. The reversal of 21111373 is 37311112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15264649 + 5846724 = 3907^2 + 2418^2 .

It is a cyclic number.

It is not a de Polignac number, because 21111373 - 2⁹ = 21110861 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21111373.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555686 + 10555687.

It is an arithmetic number, because the mean of its divisors is an integer number (10555687).

Almost surely, 2^21111373 is an apocalyptic number.

It is an amenable number.

21111373 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111373 is an equidigital number, since it uses as much as digits as its factorization.

21111373 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 126, while the sum is 19.

The square root of 21111373 is about 4594.7114164004. The cubic root of 21111373 is about 276.3792875715.

Adding to 21111373 its reverse (37311112), we get a palindrome (58422485).

The spelling of 21111373 in words is "twenty-one million, one hundred eleven thousand, three hundred seventy-three".