21343429 has 2 divisors, whose sum is σ = 21343430. Its totient is φ = 21343428.

The previous prime is 21343373. The next prime is 21343451. The reversal of 21343429 is 92434312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13890529 + 7452900 = 3727^2 + 2730^2 .

It is a cyclic number.

It is not a de Polignac number, because 21343429 - 2¹¹ = 21341381 is a prime.

It is a super-2 number, since 2×21343429² = 911083922956082, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21343397 and 21343406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21343489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10671714 + 10671715.

It is an arithmetic number, because the mean of its divisors is an integer number (10671715).

Almost surely, 2^21343429 is an apocalyptic number.

It is an amenable number.

21343429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343429 is an equidigital number, since it uses as much as digits as its factorization.

21343429 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 28.

The square root of 21343429 is about 4619.8949122247. The cubic root of 21343429 is about 277.3882524927.

It can be divided in two parts, 2 and 1343429, that added together give a palindrome (1343431).

The spelling of 21343429 in words is "twenty-one million, three hundred forty-three thousand, four hundred twenty-nine".