124004021 has 4 divisors (see below), whose sum is σ = 124082700. Its totient is φ = 123925344.

The previous prime is 124004003. The next prime is 124004071. The reversal of 124004021 is 120400421.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 118504996 + 5499025 = 10886^2 + 2345^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-124004021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 124003987 and 124004005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (124004071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36926 + ... + 40143.

It is an arithmetic number, because the mean of its divisors is an integer number (31020675).

Almost surely, 2^124004021 is an apocalyptic number.

It is an amenable number.

124004021 is a deficient number, since it is larger than the sum of its proper divisors (78679).

124004021 is an equidigital number, since it uses as much as digits as its factorization.

124004021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78678.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 124004021 is about 11135.7092724263. The cubic root of 124004021 is about 498.6684852847.

Adding to 124004021 its reverse (120400421), we get a palindrome (244404442).

The spelling of 124004021 in words is "one hundred twenty-four million, four thousand, twenty-one".