123506421 has 4 divisors (see below), whose sum is σ = 164675232. Its totient is φ = 82337612.

The previous prime is 123506419. The next prime is 123506423. The reversal of 123506421 is 124605321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (123506419) and next prime (123506423).

It is a cyclic number.

It is not a de Polignac number, because 123506421 - 2¹ = 123506419 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 123506391 and 123506400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123506423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20584401 + ... + 20584406.

It is an arithmetic number, because the mean of its divisors is an integer number (41168808).

Almost surely, 2^123506421 is an apocalyptic number.

It is an amenable number.

123506421 is a deficient number, since it is larger than the sum of its proper divisors (41168811).

123506421 is an equidigital number, since it uses as much as digits as its factorization.

123506421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41168810.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 123506421 is about 11113.3442761394. The cubic root of 123506421 is about 498.0005766029. Note that the first 3 decimals are identical.

The spelling of 123506421 in words is "one hundred twenty-three million, five hundred six thousand, four hundred twenty-one".