123230021 has 12 divisors (see below), whose sum is σ = 129435180. Its totient is φ = 117311040.

The previous prime is 123230011. The next prime is 123230027. The reversal of 123230021 is 120032321.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 77193796 + 46036225 = 8786^2 + 6785^2 .

It is a de Polignac number, because none of the positive numbers 2^k-123230021 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 = 123229978 and 123230005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123230027) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 148235 + ... + 149063.

It is an arithmetic number, because the mean of its divisors is an integer number (10786265).

Almost surely, 2^123230021 is an apocalyptic number.

It is an amenable number.

123230021 is a deficient number, since it is larger than the sum of its proper divisors (6205159).

123230021 is an equidigital number, since it uses as much as digits as its factorization.

123230021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1156 (or 1133 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 123230021 is about 11100.9018102134. The cubic root of 123230021 is about 497.6288006032.

Adding to 123230021 its reverse (120032321), we get a palindrome (243262342).

It can be divided in two parts, 1232300 and 21, that added together give a palindrome (1232321).

The spelling of 123230021 in words is "one hundred twenty-three million, two hundred thirty thousand, twenty-one".