21522814512187 has 2 divisors, whose sum is σ = 21522814512188. Its totient is φ = 21522814512186.

The previous prime is 21522814512079. The next prime is 21522814512229. The reversal of 21522814512187 is 78121541822512.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21522814512187 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21522814512187.

It is not a weakly prime, because it can be changed into another prime (21522814512487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10761407256093 + 10761407256094.

It is an arithmetic number, because the mean of its divisors is an integer number (10761407256094).

Almost surely, 2^{21522814512187} is an apocalyptic number.

21522814512187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21522814512187 is an equidigital number, since it uses as much as digits as its factorization.

21522814512187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 716800, while the sum is 49.

The spelling of 21522814512187 in words is "twenty-one trillion, five hundred twenty-two billion, eight hundred fourteen million, five hundred twelve thousand, one hundred eighty-seven".