123440404240 has 20 divisors (see below), whose sum is σ = 286998940044. Its totient is φ = 49376161664.

The previous prime is 123440404177. The next prime is 123440404259. The reversal of 123440404240 is 42404044321.

It can be written as a sum of positive squares in 2 ways, for example, as 45282137616 + 78158266624 = 212796^2 + 279568^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 123440404199 and 123440404208.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 771502447 + ... + 771502606.

Almost surely, 2^123440404240 is an apocalyptic number.

123440404240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123440404240 is an abundant number, since it is smaller than the sum of its proper divisors (163558535804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

123440404240 is a wasteful number, since it uses less digits than its factorization.

123440404240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1543005066 (or 1543005060 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 28.

Adding to 123440404240 its reverse (42404044321), we get a palindrome (165844448561).

The spelling of 123440404240 in words is "one hundred twenty-three billion, four hundred forty million, four hundred four thousand, two hundred forty".