21235212144 has 60 divisors (see below), whose sum is σ = 59822732112. Its totient is φ = 7031520000.

The previous prime is 21235212127. The next prime is 21235212157. The reversal of 21235212144 is 44121253212.

21235212144 is a `hidden beast` number, since 2 + 123 + 521 + 2 + 14 + 4 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 466557 + ... + 510044.

Almost surely, 2^21235212144 is an apocalyptic number.

21235212144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21235212144 is an abundant number, since it is smaller than the sum of its proper divisors (38587519968).

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

21235212144 is a wasteful number, since it uses less digits than its factorization.

21235212144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 976766 (or 976757 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

Adding to 21235212144 its reverse (44121253212), we get a palindrome (65356465356).

It can be divided in two parts, 212 and 35212144, that added together give a square (35212356 = 5934²).

The spelling of 21235212144 in words is "twenty-one billion, two hundred thirty-five million, two hundred twelve thousand, one hundred forty-four".