21534133540 has 12 divisors (see below), whose sum is σ = 45221680476. Its totient is φ = 8613653408.

The previous prime is 21534133513. The next prime is 21534133553. The reversal of 21534133540 is 4533143512.

It can be written as a sum of positive squares in 2 ways, for example, as 7151408356 + 14382725184 = 84566^2 + 119928^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 538353319 + ... + 538353358.

It is an arithmetic number, because the mean of its divisors is an integer number (3768473373).

Almost surely, 2^21534133540 is an apocalyptic number.

21534133540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21534133540 is an abundant number, since it is smaller than the sum of its proper divisors (23687546936).

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

21534133540 is a wasteful number, since it uses less digits than its factorization.

21534133540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1076706686 (or 1076706684 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 31.

The spelling of 21534133540 in words is "twenty-one billion, five hundred thirty-four million, one hundred thirty-three thousand, five hundred forty".