21464213 has 2 divisors, whose sum is σ = 21464214. Its totient is φ = 21464212.

The previous prime is 21464207. The next prime is 21464227. The reversal of 21464213 is 31246412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20584369 + 879844 = 4537^2 + 938^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21464213 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21464203) 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, 10732106 + 10732107.

It is an arithmetic number, because the mean of its divisors is an integer number (10732107).

Almost surely, 2^21464213 is an apocalyptic number.

It is an amenable number.

21464213 is a deficient number, since it is larger than the sum of its proper divisors (1).

21464213 is an equidigital number, since it uses as much as digits as its factorization.

21464213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 23.

The square root of 21464213 is about 4632.9486291130. The cubic root of 21464213 is about 277.9105218995.

The spelling of 21464213 in words is "twenty-one million, four hundred sixty-four thousand, two hundred thirteen".