21240131232 has 24 divisors (see below), whose sum is σ = 55755344736. Its totient is φ = 7080043712.

The previous prime is 21240131197. The next prime is 21240131233. The reversal of 21240131232 is 23213104212.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×21240131232² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21240131199 and 21240131208.

It is not an unprimeable number, because it can be changed into a prime (21240131233) 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, 110625588 + ... + 110625779.

It is an arithmetic number, because the mean of its divisors is an integer number (2323139364).

Almost surely, 2^21240131232 is an apocalyptic number.

It is an amenable number.

21240131232 is an abundant number, since it is smaller than the sum of its proper divisors (34515213504).

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

21240131232 is a wasteful number, since it uses less digits than its factorization.

21240131232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221251380 (or 221251372 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21240131232 its reverse (23213104212), we get a palindrome (44453235444).

The spelling of 21240131232 in words is "twenty-one billion, two hundred forty million, one hundred thirty-one thousand, two hundred thirty-two".