21963313 has 2 divisors, whose sum is σ = 21963314. Its totient is φ = 21963312.

The previous prime is 21963287. The next prime is 21963317. The reversal of 21963313 is 31336912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18249984 + 3713329 = 4272^2 + 1927^2 .

It is a cyclic number.

It is not a de Polignac number, because 21963313 - 2¹³ = 21955121 is a prime.

It is not a weakly prime, because it can be changed into another prime (21963317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10981656 + 10981657.

It is an arithmetic number, because the mean of its divisors is an integer number (10981657).

Almost surely, 2^21963313 is an apocalyptic number.

It is an amenable number.

21963313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21963313 is an equidigital number, since it uses as much as digits as its factorization.

21963313 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2916, while the sum is 28.

The square root of 21963313 is about 4686.5032806987. The cubic root of 21963313 is about 280.0480912294.

The spelling of 21963313 in words is "twenty-one million, nine hundred sixty-three thousand, three hundred thirteen".