23145221 has 4 divisors (see below), whose sum is σ = 25249344. Its totient is φ = 21041100.

The previous prime is 23145209. The next prime is 23145271. The reversal of 23145221 is 12254132.

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 not a de Polignac number, because 23145221 - 2¹⁴ = 23128837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23145193 and 23145202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23145271) 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, 1052045 + ... + 1052066.

It is an arithmetic number, because the mean of its divisors is an integer number (6312336).

Almost surely, 2^23145221 is an apocalyptic number.

It is an amenable number.

23145221 is a deficient number, since it is larger than the sum of its proper divisors (2104123).

23145221 is a wasteful number, since it uses less digits than its factorization.

23145221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2104122.

The product of its digits is 480, while the sum is 20.

The square root of 23145221 is about 4810.9480354708. The cubic root of 23145221 is about 284.9839777594.

Adding to 23145221 its reverse (12254132), we get a palindrome (35399353).

The spelling of 23145221 in words is "twenty-three million, one hundred forty-five thousand, two hundred twenty-one".