123421 has 4 divisors (see below), whose sum is σ = 124992. Its totient is φ = 121852.

The previous prime is 123419. The next prime is 123427. The reversal of 123421 is 124321.

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 a cyclic number.

It is not a de Polignac number, because 123421 - 2¹ = 123419 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 (123427) 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, 661 + ... + 826.

It is an arithmetic number, because the mean of its divisors is an integer number (31248).

2¹²³⁴²¹ is an apocalyptic number.

It is an amenable number.

123421 is a deficient number, since it is larger than the sum of its proper divisors (1571).

123421 is an equidigital number, since it uses as much as digits as its factorization.

123421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1570.

The product of its digits is 48, while the sum is 13.

The square root of 123421 is about 351.3132505329. The cubic root of 123421 is about 49.7885739069.

Adding to 123421 its reverse (124321), we get a palindrome (247742).

Subtracting 123421 from its reverse (124321), we obtain a square (900 = 30²).

The spelling of 123421 in words is "one hundred twenty-three thousand, four hundred twenty-one", and thus it is an iban number.