21323145 has 8 divisors (see below), whose sum is σ = 34117056. Its totient is φ = 11372336.

The previous prime is 21323129. The next prime is 21323153. The reversal of 21323145 is 54132312.

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 21323145 - 2⁴ = 21323129 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 710757 + ... + 710786.

It is an arithmetic number, because the mean of its divisors is an integer number (4264632).

Almost surely, 2^21323145 is an apocalyptic number.

It is an amenable number.

21323145 is a deficient number, since it is larger than the sum of its proper divisors (12793911).

21323145 is a wasteful number, since it uses less digits than its factorization.

21323145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1421551.

The product of its digits is 720, while the sum is 21.

The square root of 21323145 is about 4617.6991023669. The cubic root of 21323145 is about 277.3003514862.

Adding to 21323145 its reverse (54132312), we get a palindrome (75455457).

The spelling of 21323145 in words is "twenty-one million, three hundred twenty-three thousand, one hundred forty-five".