21203134424 has 32 divisors (see below), whose sum is σ = 40237298640. Its totient is φ = 10473648000.

The previous prime is 21203134423. The next prime is 21203134471. The reversal of 21203134424 is 42443130212.

It is a junction number, because it is equal to n+sod(n) for n = 21203134393 and 21203134402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203134423) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 344027 + ... + 400949.

Almost surely, 2^21203134424 is an apocalyptic number.

It is an amenable number.

21203134424 is a deficient number, since it is larger than the sum of its proper divisors (19034164216).

21203134424 is a wasteful number, since it uses less digits than its factorization.

21203134424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57491 (or 57487 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 21203134424 its reverse (42443130212), we get a palindrome (63646264636).

The spelling of 21203134424 in words is "twenty-one billion, two hundred three million, one hundred thirty-four thousand, four hundred twenty-four".