123131345 has 4 divisors (see below), whose sum is σ = 147757620. Its totient is φ = 98505072.

The previous prime is 123131339. The next prime is 123131347. The reversal of 123131345 is 543131321.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 56415121 + 66716224 = 7511^2 + 8168^2 .

It is a cyclic number.

It is not a de Polignac number, because 123131345 - 2⁴ = 123131329 is a prime.

It is a super-2 number, since 2×123131345² = 30322656243018050, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 123131345.

It is not an unprimeable number, because it can be changed into a prime (123131347) 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, 12313130 + ... + 12313139.

It is an arithmetic number, because the mean of its divisors is an integer number (36939405).

Almost surely, 2^123131345 is an apocalyptic number.

It is an amenable number.

123131345 is a deficient number, since it is larger than the sum of its proper divisors (24626275).

123131345 is an equidigital number, since it uses as much as digits as its factorization.

123131345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24626274.

The product of its digits is 1080, while the sum is 23.

The square root of 123131345 is about 11096.4564163520. The cubic root of 123131345 is about 497.4959403051.

Adding to 123131345 its reverse (543131321), we get a palindrome (666262666).

The spelling of 123131345 in words is "one hundred twenty-three million, one hundred thirty-one thousand, three hundred forty-five".