21098126017 has 2 divisors, whose sum is σ = 21098126018. Its totient is φ = 21098126016.

The previous prime is 21098126011. The next prime is 21098126057. The reversal of 21098126017 is 71062189012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21087686656 + 10439361 = 145216^2 + 3231^2 .

It is a cyclic number.

It is not a de Polignac number, because 21098126017 - 2³ = 21098126009 is a prime.

It is not a weakly prime, because it can be changed into another prime (21098126011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10549063008 + 10549063009.

It is an arithmetic number, because the mean of its divisors is an integer number (10549063009).

Almost surely, 2^21098126017 is an apocalyptic number.

It is an amenable number.

21098126017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21098126017 is an equidigital number, since it uses as much as digits as its factorization.

21098126017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 37.

The spelling of 21098126017 in words is "twenty-one billion, ninety-eight million, one hundred twenty-six thousand, seventeen".