21510271551499 has 2 divisors, whose sum is σ = 21510271551500. Its totient is φ = 21510271551498.

The previous prime is 21510271551491. The next prime is 21510271551547. The reversal of 21510271551499 is 99415517201512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21510271551499 - 2³ = 21510271551491 is a prime.

It is not a weakly prime, because it can be changed into another prime (21510271551491) by changing a digit.

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 as a sum of consecutive naturals, namely, 10755135775749 + 10755135775750.

It is an arithmetic number, because the mean of its divisors is an integer number (10755135775750).

Almost surely, 2^{21510271551499} is an apocalyptic number.

21510271551499 is a deficient number, since it is larger than the sum of its proper divisors (1).

21510271551499 is an equidigital number, since it uses as much as digits as its factorization.

21510271551499 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1134000, while the sum is 52.

The spelling of 21510271551499 in words is "twenty-one trillion, five hundred ten billion, two hundred seventy-one million, five hundred fifty-one thousand, four hundred ninety-nine".