23238821 has 4 divisors (see below), whose sum is σ = 23733312. Its totient is φ = 22744332.

The previous prime is 23238793. The next prime is 23238833. The reversal of 23238821 is 12883232.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23238821 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 (23237821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 247175 + ... + 247268.

It is an arithmetic number, because the mean of its divisors is an integer number (5933328).

Almost surely, 2^23238821 is an apocalyptic number.

It is an amenable number.

23238821 is a deficient number, since it is larger than the sum of its proper divisors (494491).

23238821 is an equidigital number, since it uses as much as digits as its factorization.

23238821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 494490.

The product of its digits is 4608, while the sum is 29.

The square root of 23238821 is about 4820.6660328216. Note that the first 3 decimals coincide. The cubic root of 23238821 is about 285.3676224490.

The spelling of 23238821 in words is "twenty-three million, two hundred thirty-eight thousand, eight hundred twenty-one".