123404531 has 4 divisors (see below), whose sum is σ = 124305432. Its totient is φ = 122503632.

The previous prime is 123404497. The next prime is 123404537. The reversal of 123404531 is 135404321.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123404531 is a prime.

It is a super-2 number, since 2×123404531² = 30457356542659922, 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 = 123404497 and 123404506.

It is not an unprimeable number, because it can be changed into a prime (123404537) 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, 450245 + ... + 450518.

It is an arithmetic number, because the mean of its divisors is an integer number (31076358).

Almost surely, 2^123404531 is an apocalyptic number.

123404531 is a deficient number, since it is larger than the sum of its proper divisors (900901).

123404531 is an equidigital number, since it uses as much as digits as its factorization.

123404531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 900900.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 123404531 is about 11108.7592016390. The cubic root of 123404531 is about 497.8635925277.

Adding to 123404531 its reverse (135404321), we get a palindrome (258808852).

The spelling of 123404531 in words is "one hundred twenty-three million, four hundred four thousand, five hundred thirty-one".