21343659 has 4 divisors (see below), whose sum is σ = 28458216. Its totient is φ = 14229104.

The previous prime is 21343649. The next prime is 21343661. The reversal of 21343659 is 95634312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21343659 - 2⁴ = 21343643 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21343649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3557274 + ... + 3557279.

It is an arithmetic number, because the mean of its divisors is an integer number (7114554).

Almost surely, 2^21343659 is an apocalyptic number.

21343659 is a deficient number, since it is larger than the sum of its proper divisors (7114557).

21343659 is an equidigital number, since it uses as much as digits as its factorization.

21343659 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7114556.

The product of its digits is 19440, while the sum is 33.

The square root of 21343659 is about 4619.9198044988. The cubic root of 21343659 is about 277.3892488816.

The spelling of 21343659 in words is "twenty-one million, three hundred forty-three thousand, six hundred fifty-nine".