12123621 has 16 divisors (see below), whose sum is σ = 18209920. Its totient is φ = 7970400.

The previous prime is 12123607. The next prime is 12123637. The reversal of 12123621 is 12632121.

12123621 is a `hidden beast` number, since 1 + 21 + 23 + 621 = 666.

It is not a de Polignac number, because 12123621 - 2⁵ = 12123589 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12123594 and 12123603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12123521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1105 + ... + 5046.

It is an arithmetic number, because the mean of its divisors is an integer number (1138120).

Almost surely, 2^12123621 is an apocalyptic number.

It is an amenable number.

12123621 is a deficient number, since it is larger than the sum of its proper divisors (6086299).

12123621 is an equidigital number, since it uses as much as digits as its factorization.

12123621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6233 (or 6227 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 12123621 is about 3481.8990508055. The cubic root of 12123621 is about 229.7263348746.

Adding to 12123621 its reverse (12632121), we get a palindrome (24755742).

The spelling of 12123621 in words is "twelve million, one hundred twenty-three thousand, six hundred twenty-one".