13121345 has 4 divisors (see below), whose sum is σ = 15745620. Its totient is φ = 10497072.

The previous prime is 13121341. The next prime is 13121371. The reversal of 13121345 is 54312131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54312131 = 23 ⋅2361397.

It can be written as a sum of positive squares in 2 ways, for example, as 9461776 + 3659569 = 3076^2 + 1913^2 .

It is a cyclic number.

It is not a de Polignac number, because 13121345 - 2² = 13121341 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13121341) 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, 1312130 + ... + 1312139.

It is an arithmetic number, because the mean of its divisors is an integer number (3936405).

Almost surely, 2^13121345 is an apocalyptic number.

It is an amenable number.

13121345 is a deficient number, since it is larger than the sum of its proper divisors (2624275).

13121345 is an equidigital number, since it uses as much as digits as its factorization.

13121345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2624274.

The product of its digits is 360, while the sum is 20.

The square root of 13121345 is about 3622.3397135001. The cubic root of 13121345 is about 235.8628008922.

Adding to 13121345 its reverse (54312131), we get a palindrome (67433476).

The spelling of 13121345 in words is "thirteen million, one hundred twenty-one thousand, three hundred forty-five".