21312200989 has 2 divisors, whose sum is σ = 21312200990. Its totient is φ = 21312200988.

The previous prime is 21312200963. The next prime is 21312200999. The reversal of 21312200989 is 98900221312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15211028889 + 6101172100 = 123333^2 + 78110^2 .

It is a cyclic number.

It is not a de Polignac number, because 21312200989 - 2⁹ = 21312200477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21312200999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656100494 + 10656100495.

It is an arithmetic number, because the mean of its divisors is an integer number (10656100495).

Almost surely, 2^21312200989 is an apocalyptic number.

It is an amenable number.

21312200989 is a deficient number, since it is larger than the sum of its proper divisors (1).

21312200989 is an equidigital number, since it uses as much as digits as its factorization.

21312200989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 37.

The spelling of 21312200989 in words is "twenty-one billion, three hundred twelve million, two hundred thousand, nine hundred eighty-nine".