21531355330343 has 2 divisors, whose sum is σ = 21531355330344. Its totient is φ = 21531355330342.

The previous prime is 21531355330319. The next prime is 21531355330361. The reversal of 21531355330343 is 34303355313512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21531355330343 - 2¹⁶ = 21531355264807 is a prime.

It is a super-2 number, since 2×21531355330343² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21531355330343.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21531355330363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10765677665171 + 10765677665172.

It is an arithmetic number, because the mean of its divisors is an integer number (10765677665172).

Almost surely, 2^{21531355330343} is an apocalyptic number.

21531355330343 is a deficient number, since it is larger than the sum of its proper divisors (1).

21531355330343 is an equidigital number, since it uses as much as digits as its factorization.

21531355330343 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 729000, while the sum is 41.

The spelling of 21531355330343 in words is "twenty-one trillion, five hundred thirty-one billion, three hundred fifty-five million, three hundred thirty thousand, three hundred forty-three".