21413369 has 2 divisors, whose sum is σ = 21413370. Its totient is φ = 21413368.

The previous prime is 21413303. The next prime is 21413389. The reversal of 21413369 is 96331412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13601344 + 7812025 = 3688^2 + 2795^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21413369 is a prime.

It is a super-2 number, since 2×21413369² = 917064743860322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21413389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10706684 + 10706685.

It is an arithmetic number, because the mean of its divisors is an integer number (10706685).

Almost surely, 2^21413369 is an apocalyptic number.

It is an amenable number.

21413369 is a deficient number, since it is larger than the sum of its proper divisors (1).

21413369 is an equidigital number, since it uses as much as digits as its factorization.

21413369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 29.

The square root of 21413369 is about 4627.4581575634. The cubic root of 21413369 is about 277.6909121037.

The spelling of 21413369 in words is "twenty-one million, four hundred thirteen thousand, three hundred sixty-nine".