23722221 has 16 divisors (see below), whose sum is σ = 32431104. Its totient is φ = 15419184.

The previous prime is 23722219. The next prime is 23722247. The reversal of 23722221 is 12222732.

It is a happy number.

It is not a de Polignac number, because 23722221 - 2¹ = 23722219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23722211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20956 + ... + 22058.

It is an arithmetic number, because the mean of its divisors is an integer number (2026944).

Almost surely, 2^23722221 is an apocalyptic number.

It is an amenable number.

23722221 is a deficient number, since it is larger than the sum of its proper divisors (8708883).

23722221 is a wasteful number, since it uses less digits than its factorization.

23722221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1280.

The product of its digits is 672, while the sum is 21.

The square root of 23722221 is about 4870.5462732634. The cubic root of 23722221 is about 287.3327410238.

Adding to 23722221 its reverse (12222732), we get a palindrome (35944953).

The spelling of 23722221 in words is "twenty-three million, seven hundred twenty-two thousand, two hundred twenty-one".