123124021 has 2 divisors, whose sum is σ = 123124022. Its totient is φ = 123124020.

The previous prime is 123124019. The next prime is 123124031. The reversal of 123124021 is 120421321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122544900 + 579121 = 11070^2 + 761^2 .

It is a cyclic number.

It is not a de Polignac number, because 123124021 - 2¹ = 123124019 is a prime.

Together with 123124019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 123123986 and 123124004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123124031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61562010 + 61562011.

It is an arithmetic number, because the mean of its divisors is an integer number (61562011).

Almost surely, 2^123124021 is an apocalyptic number.

It is an amenable number.

123124021 is a deficient number, since it is larger than the sum of its proper divisors (1).

123124021 is an equidigital number, since it uses as much as digits as its factorization.

123124021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 123124021 is about 11096.1263961799. The cubic root of 123124021 is about 497.4860762245.

Adding to 123124021 its reverse (120421321), we get a palindrome (243545342).

It can be divided in two parts, 1231 and 24021, that added together give a palindrome (25252).

The spelling of 123124021 in words is "one hundred twenty-three million, one hundred twenty-four thousand, twenty-one".