21575687212889 has 2 divisors, whose sum is σ = 21575687212890. Its totient is φ = 21575687212888.

The previous prime is 21575687212787. The next prime is 21575687212897. The reversal of 21575687212889 is 98821278657512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16897788718864 + 4677898494025 = 4110692^2 + 2162845^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21575687212889 is a prime.

It is not a weakly prime, because it can be changed into another prime (21575687214889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10787843606444 + 10787843606445.

It is an arithmetic number, because the mean of its divisors is an integer number (10787843606445).

Almost surely, 2^{21575687212889} is an apocalyptic number.

It is an amenable number.

21575687212889 is a deficient number, since it is larger than the sum of its proper divisors (1).

21575687212889 is an equidigital number, since it uses as much as digits as its factorization.

21575687212889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 270950400, while the sum is 71.

The spelling of 21575687212889 in words is "twenty-one trillion, five hundred seventy-five billion, six hundred eighty-seven million, two hundred twelve thousand, eight hundred eighty-nine".