21015240532 has 48 divisors (see below), whose sum is σ = 44211004992. Its totient is φ = 8612513280.

The previous prime is 21015240517. The next prime is 21015240577. The reversal of 21015240532 is 23504251012.

It is a junction number, because it is equal to n+sod(n) for n = 21015240497 and 21015240506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 402613 + ... + 451804.

It is an arithmetic number, because the mean of its divisors is an integer number (921062604).

Almost surely, 2^21015240532 is an apocalyptic number.

21015240532 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21015240532 is an abundant number, since it is smaller than the sum of its proper divisors (23195764460).

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

21015240532 is a wasteful number, since it uses less digits than its factorization.

21015240532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 854488 (or 854486 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

Adding to 21015240532 its reverse (23504251012), we get a palindrome (44519491544).

The spelling of 21015240532 in words is "twenty-one billion, fifteen million, two hundred forty thousand, five hundred thirty-two".