21503521513340 has 24 divisors (see below), whose sum is σ = 45158554134960. Its totient is φ = 8601187851648.

The previous prime is 21503521513301. The next prime is 21503521513361. The reversal of 21503521513340 is 4331512530512.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21503521513340.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12997217 + ... + 14557976.

It is an arithmetic number, because the mean of its divisors is an integer number (1881606422290).

Almost surely, 2^{21503521513340} is an apocalyptic number.

21503521513340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21503521513340 is an abundant number, since it is smaller than the sum of its proper divisors (23655032621620).

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

21503521513340 is a wasteful number, since it uses less digits than its factorization.

21503521513340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27594221 (or 27594219 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 35.

The spelling of 21503521513340 in words is "twenty-one trillion, five hundred three billion, five hundred twenty-one million, five hundred thirteen thousand, three hundred forty".