123315431 has 4 divisors (see below), whose sum is σ = 124406832. Its totient is φ = 122224032.

The previous prime is 123315403. The next prime is 123315449. The reversal of 123315431 is 134513321.

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

It is a cyclic number.

It is not a de Polignac number, because 123315431 - 2¹⁰ = 123314407 is a prime.

It is a super-2 number, since 2×123315431² = 30413391045431522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 123315397 and 123315406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123315461) 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, 545531 + ... + 545756.

It is an arithmetic number, because the mean of its divisors is an integer number (31101708).

Almost surely, 2^123315431 is an apocalyptic number.

123315431 is a deficient number, since it is larger than the sum of its proper divisors (1091401).

123315431 is a wasteful number, since it uses less digits than its factorization.

123315431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1091400.

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

The square root of 123315431 is about 11104.7481286160. The cubic root of 123315431 is about 497.7437419135.

Adding to 123315431 its reverse (134513321), we get a palindrome (257828752).

The spelling of 123315431 in words is "one hundred twenty-three million, three hundred fifteen thousand, four hundred thirty-one".