21001098132881 has 2 divisors, whose sum is σ = 21001098132882. Its totient is φ = 21001098132880.

The previous prime is 21001098132727. The next prime is 21001098132893. The reversal of 21001098132881 is 18823189010012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17311590918400 + 3689507214481 = 4160720^2 + 1920809^2 .

It is a cyclic number.

It is not a de Polignac number, because 21001098132881 - 2¹⁴ = 21001098116497 is a prime.

It is a super-2 number, since 2×21001098132881² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21001098132481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500549066440 + 10500549066441.

It is an arithmetic number, because the mean of its divisors is an integer number (10500549066441).

Almost surely, 2^{21001098132881} is an apocalyptic number.

It is an amenable number.

21001098132881 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001098132881 is an equidigital number, since it uses as much as digits as its factorization.

21001098132881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 55296, while the sum is 44.

The spelling of 21001098132881 in words is "twenty-one trillion, one billion, ninety-eight million, one hundred thirty-two thousand, eight hundred eighty-one".