21408301 has 2 divisors, whose sum is σ = 21408302. Its totient is φ = 21408300.

The previous prime is 21408251. The next prime is 21408319. The reversal of 21408301 is 10380412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11492100 + 9916201 = 3390^2 + 3149^2 .

It is a cyclic number.

It is not a de Polignac number, because 21408301 - 2⁷ = 21408173 is a prime.

It is a super-3 number, since 3×21408301³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21408341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10704150 + 10704151.

It is an arithmetic number, because the mean of its divisors is an integer number (10704151).

Almost surely, 2^21408301 is an apocalyptic number.

It is an amenable number.

21408301 is a deficient number, since it is larger than the sum of its proper divisors (1).

21408301 is an equidigital number, since it uses as much as digits as its factorization.

21408301 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 21408301 is about 4626.9105243132. The cubic root of 21408301 is about 277.6690029157.

Adding to 21408301 its reverse (10380412), we get a palindrome (31788713).

The spelling of 21408301 in words is "twenty-one million, four hundred eight thousand, three hundred one".