21505134332 has 48 divisors (see below), whose sum is σ = 41610530304. Its totient is φ = 9643200000.

The previous prime is 21505134307. The next prime is 21505134373. The reversal of 21505134332 is 23343150512.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21505134295 and 21505134304.

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, 2738732 + ... + 2746572.

It is an arithmetic number, because the mean of its divisors is an integer number (866886048).

Almost surely, 2^21505134332 is an apocalyptic number.

21505134332 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21505134332 is a deficient number, since it is larger than the sum of its proper divisors (20105395972).

21505134332 is a wasteful number, since it uses less digits than its factorization.

21505134332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8690 (or 8688 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 29.

Adding to 21505134332 its reverse (23343150512), we get a palindrome (44848284844).

The spelling of 21505134332 in words is "twenty-one billion, five hundred five million, one hundred thirty-four thousand, three hundred thirty-two".