21230012144 has 40 divisors (see below), whose sum is σ = 46085310768. Its totient is φ = 9389191680.

The previous prime is 21230012143. The next prime is 21230012173. The reversal of 21230012144 is 44121003212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21230012143) 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, 1623557 + ... + 1636580.

Almost surely, 2^21230012144 is an apocalyptic number.

It is an amenable number.

21230012144 is an abundant number, since it is smaller than the sum of its proper divisors (24855298624).

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

21230012144 is a wasteful number, since it uses less digits than its factorization.

21230012144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3260193 (or 3260187 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21230012144 its reverse (44121003212), we get a palindrome (65351015356).

The spelling of 21230012144 in words is "twenty-one billion, two hundred thirty million, twelve thousand, one hundred forty-four".