21324407 has 8 divisors (see below), whose sum is σ = 23131920. Its totient is φ = 19540800.

The previous prime is 21324389. The next prime is 21324419. The reversal of 21324407 is 70442312.

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 21324407 - 2¹² = 21320311 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21324467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4094 + ... + 7707.

It is an arithmetic number, because the mean of its divisors is an integer number (2891490).

Almost surely, 2^21324407 is an apocalyptic number.

21324407 is a deficient number, since it is larger than the sum of its proper divisors (1807513).

21324407 is a wasteful number, since it uses less digits than its factorization.

21324407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11953.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 21324407 is about 4617.8357484865. The cubic root of 21324407 is about 277.3058220072.

Adding to 21324407 its reverse (70442312), we get a palindrome (91766719).

The spelling of 21324407 in words is "twenty-one million, three hundred twenty-four thousand, four hundred seven".