123630021 has 12 divisors (see below), whose sum is σ = 178699872. Its totient is φ = 82363176.

The previous prime is 123630019. The next prime is 123630029. The reversal of 123630021 is 120036321.

123630021 is a `hidden beast` number, since 12 + 3 + 630 + 0 + 21 = 666.

It is not a de Polignac number, because 123630021 - 2¹ = 123630019 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 123629976 and 123630003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123630029) 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, 12240 + ... + 19926.

It is an arithmetic number, because the mean of its divisors is an integer number (14891656).

Almost surely, 2^123630021 is an apocalyptic number.

It is an amenable number.

123630021 is a deficient number, since it is larger than the sum of its proper divisors (55069851).

123630021 is a wasteful number, since it uses less digits than its factorization.

123630021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9480 (or 9477 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 123630021 is about 11118.9037679081. The cubic root of 123630021 is about 498.1666471846.

Adding to 123630021 its reverse (120036321), we get a palindrome (243666342).

It can be divided in two parts, 1236300 and 21, that added together give a palindrome (1236321).

The spelling of 123630021 in words is "one hundred twenty-three million, six hundred thirty thousand, twenty-one".