12128906 has 4 divisors (see below), whose sum is σ = 18193362. Its totient is φ = 6064452.

The previous prime is 12128903. The next prime is 12128911. The reversal of 12128906 is 60982121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60982121 = 109 ⋅559469.

It can be written as a sum of positive squares in only one way, i.e., 8673025 + 3455881 = 2945^2 + 1859^2 .

It is a super-2 number, since 2×12128906² = 294220721513672, which contains 22 as substring.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (12128903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3032225 + ... + 3032228.

Almost surely, 2^12128906 is an apocalyptic number.

12128906 is a deficient number, since it is larger than the sum of its proper divisors (6064456).

12128906 is an equidigital number, since it uses as much as digits as its factorization.

12128906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6064455.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 12128906 is about 3482.6578930466. The cubic root of 12128906 is about 229.7597112425.

The spelling of 12128906 in words is "twelve million, one hundred twenty-eight thousand, nine hundred six".