232100021 has 6 divisors (see below), whose sum is σ = 240380322. Its totient is φ = 224095760.

The previous prime is 232099999. The next prime is 232100027. The reversal of 232100021 is 120001232.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 65431921 + 166668100 = 8089^2 + 12910^2 .

It is not a de Polignac number, because 232100021 - 2⁶ = 232099957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 232099975 and 232100011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (232100027) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 137150 + ... + 138831.

It is an arithmetic number, because the mean of its divisors is an integer number (40063387).

Almost surely, 2^232100021 is an apocalyptic number.

It is an amenable number.

232100021 is a deficient number, since it is larger than the sum of its proper divisors (8280301).

232100021 is an equidigital number, since it uses as much as digits as its factorization.

232100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276039 (or 276010 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 232100021 is about 15234.8292081008. The cubic root of 232100021 is about 614.5516559564.

Adding to 232100021 its reverse (120001232), we get a palindrome (352101253).

The spelling of 232100021 in words is "two hundred thirty-two million, one hundred thousand, twenty-one".