21530400450511 has 2 divisors, whose sum is σ = 21530400450512. Its totient is φ = 21530400450510.

The previous prime is 21530400450509. The next prime is 21530400450527. The reversal of 21530400450511 is 11505400403512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21530400450511 - 2¹ = 21530400450509 is a prime.

It is a super-3 number, since 3×21530400450511³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 21530400450509, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21500400450511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10765200225255 + 10765200225256.

It is an arithmetic number, because the mean of its divisors is an integer number (10765200225256).

Almost surely, 2^{21530400450511} is an apocalyptic number.

21530400450511 is a deficient number, since it is larger than the sum of its proper divisors (1).

21530400450511 is an equidigital number, since it uses as much as digits as its factorization.

21530400450511 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12000, while the sum is 31.

The spelling of 21530400450511 in words is "twenty-one trillion, five hundred thirty billion, four hundred million, four hundred fifty thousand, five hundred eleven".