21423353 has 8 divisors (see below), whose sum is σ = 24511872. Its totient is φ = 18341856.

The previous prime is 21423343. The next prime is 21423359. The reversal of 21423353 is 35332412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21423353 - 2²² = 17229049 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21423359) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10676 + ... + 12522.

It is an arithmetic number, because the mean of its divisors is an integer number (3063984).

Almost surely, 2^21423353 is an apocalyptic number.

It is an amenable number.

21423353 is a deficient number, since it is larger than the sum of its proper divisors (3088519).

21423353 is a wasteful number, since it uses less digits than its factorization.

21423353 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3511.

The product of its digits is 2160, while the sum is 23.

The square root of 21423353 is about 4628.5368098353. The cubic root of 21423353 is about 277.7340632661.

Adding to 21423353 its reverse (35332412), we get a palindrome (56755765).

The spelling of 21423353 in words is "twenty-one million, four hundred twenty-three thousand, three hundred fifty-three".