123924221 has 4 divisors (see below), whose sum is σ = 128197500. Its totient is φ = 119650944.

The previous prime is 123924191. The next prime is 123924239. The reversal of 123924221 is 122429321.

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 72012196 + 51912025 = 8486^2 + 7205^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123924221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123921221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2136596 + ... + 2136653.

It is an arithmetic number, because the mean of its divisors is an integer number (32049375).

Almost surely, 2^123924221 is an apocalyptic number.

It is an amenable number.

123924221 is a deficient number, since it is larger than the sum of its proper divisors (4273279).

123924221 is an equidigital number, since it uses as much as digits as its factorization.

123924221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4273278.

The product of its digits is 1728, while the sum is 26.

The square root of 123924221 is about 11132.1256281089. The cubic root of 123924221 is about 498.5614933663.

The spelling of 123924221 in words is "one hundred twenty-three million, nine hundred twenty-four thousand, two hundred twenty-one".