21230131424 has 24 divisors (see below), whose sum is σ = 42505245720. Its totient is φ = 10435148416.

The previous prime is 21230131399. The next prime is 21230131427. The reversal of 21230131424 is 42413103212.

It is a self number, because there is not a number n which added to its sum of digits gives 21230131424.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21230131427) 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, 5620499 + ... + 5624274.

It is an arithmetic number, because the mean of its divisors is an integer number (1771051905).

Almost surely, 2^21230131424 is an apocalyptic number.

It is an amenable number.

21230131424 is an abundant number, since it is smaller than the sum of its proper divisors (21275114296).

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

21230131424 is a wasteful number, since it uses less digits than its factorization.

21230131424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11244842 (or 11244834 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 21230131424 its reverse (42413103212), we get a palindrome (63643234636).

The spelling of 21230131424 in words is "twenty-one billion, two hundred thirty million, one hundred thirty-one thousand, four hundred twenty-four".