20400424424 has 16 divisors (see below), whose sum is σ = 38409516420. Its totient is φ = 10157886720.

The previous prime is 20400424423. The next prime is 20400424453. The reversal of 20400424424 is 42442400402.

It can be written as a sum of positive squares in 2 ways, for example, as 18031655524 + 2368768900 = 134282^2 + 48670^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20400424393 and 20400424402.

It is not an unprimeable number, because it can be changed into a prime (20400424423) 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, 5288639 + ... + 5292494.

Almost surely, 2^20400424424 is an apocalyptic number.

It is an amenable number.

20400424424 is a deficient number, since it is larger than the sum of its proper divisors (18009091996).

20400424424 is a wasteful number, since it uses less digits than its factorization.

20400424424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10581380 (or 10581376 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 26.

Adding to 20400424424 its reverse (42442400402), we get a palindrome (62842824826).

The spelling of 20400424424 in words is "twenty billion, four hundred million, four hundred twenty-four thousand, four hundred twenty-four".