12123345 has 16 divisors (see below), whose sum is σ = 20889792. Its totient is φ = 5968320.

The previous prime is 12123341. The next prime is 12123359. The reversal of 12123345 is 54332121.

It is not a de Polignac number, because 12123345 - 2² = 12123341 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12123341) 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, 30891 + ... + 31280.

It is an arithmetic number, because the mean of its divisors is an integer number (1305612).

Almost surely, 2^12123345 is an apocalyptic number.

12123345 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12123345 is a deficient number, since it is larger than the sum of its proper divisors (8766447).

12123345 is a wasteful number, since it uses less digits than its factorization.

12123345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62192.

The product of its digits is 720, while the sum is 21.

The square root of 12123345 is about 3481.8594170357. The cubic root of 12123345 is about 229.7245915849.

Adding to 12123345 its reverse (54332121), we get a palindrome (66455466).

It can be divided in two parts, 121233 and 45, that added together give a triangular number (121278 = T₄₉₂).

The spelling of 12123345 in words is "twelve million, one hundred twenty-three thousand, three hundred forty-five".