21201211010989 has 2 divisors, whose sum is σ = 21201211010990. Its totient is φ = 21201211010988.

The previous prime is 21201211010983. The next prime is 21201211011049. The reversal of 21201211010989 is 98901011210212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13657718053225 + 7543492957764 = 3695635^2 + 2746542^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201211010989 - 2³ = 21201211010981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21201211010981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600605505494 + 10600605505495.

It is an arithmetic number, because the mean of its divisors is an integer number (10600605505495).

Almost surely, 2^{21201211010989} is an apocalyptic number.

It is an amenable number.

21201211010989 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201211010989 is an equidigital number, since it uses as much as digits as its factorization.

21201211010989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 37.

The spelling of 21201211010989 in words is "twenty-one trillion, two hundred one billion, two hundred eleven million, ten thousand, nine hundred eighty-nine".