23121205 has 4 divisors (see below), whose sum is σ = 27745452. Its totient is φ = 18496960.

The previous prime is 23121193. The next prime is 23121209. The reversal of 23121205 is 50212132.

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

It can be written as a sum of positive squares in 2 ways, for example, as 7193124 + 15928081 = 2682^2 + 3991^2 .

It is a de Polignac number, because none of the positive numbers 2^k-23121205 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 (23121209) 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, 2312116 + ... + 2312125.

It is an arithmetic number, because the mean of its divisors is an integer number (6936363).

Almost surely, 2^23121205 is an apocalyptic number.

It is an amenable number.

23121205 is a deficient number, since it is larger than the sum of its proper divisors (4624247).

23121205 is an equidigital number, since it uses as much as digits as its factorization.

23121205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4624246.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 23121205 is about 4808.4514139170. The cubic root of 23121205 is about 284.8853750601.

Adding to 23121205 its reverse (50212132), we get a palindrome (73333337).

The spelling of 23121205 in words is "twenty-three million, one hundred twenty-one thousand, two hundred five".