21502023133321 has 8 divisors (see below), whose sum is σ = 21544163055944. Its totient is φ = 21459892049280.

The previous prime is 21502023133319. The next prime is 21502023133333. The reversal of 21502023133321 is 12333132020512.

It can be written as a sum of positive squares in 4 ways, for example, as 10315246096 + 21491707887225 = 101564^2 + 4635915^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21502023133321 - 2¹ = 21502023133319 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21502023133321.

It is not an unprimeable number, because it can be changed into a prime (21502023233321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2671165 + ... + 7080901.

It is an arithmetic number, because the mean of its divisors is an integer number (2693020381993).

Almost surely, 2^{21502023133321} is an apocalyptic number.

It is an amenable number.

21502023133321 is a deficient number, since it is larger than the sum of its proper divisors (42139922623).

21502023133321 is an equidigital number, since it uses as much as digits as its factorization.

21502023133321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4419291.

The product of its (nonzero) digits is 6480, while the sum is 28.

Adding to 21502023133321 its reverse (12333132020512), we get a palindrome (33835155153833).

The spelling of 21502023133321 in words is "twenty-one trillion, five hundred two billion, twenty-three million, one hundred thirty-three thousand, three hundred twenty-one".