21310229989 has 2 divisors, whose sum is σ = 21310229990. Its totient is φ = 21310229988.

The previous prime is 21310229981. The next prime is 21310230023. The reversal of 21310229989 is 98992201312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11019750625 + 10290479364 = 104975^2 + 101442^2 .

It is a cyclic number.

It is not a de Polignac number, because 21310229989 - 2³ = 21310229981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21310229981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10655114994 + 10655114995.

It is an arithmetic number, because the mean of its divisors is an integer number (10655114995).

Almost surely, 2^21310229989 is an apocalyptic number.

It is an amenable number.

21310229989 is a deficient number, since it is larger than the sum of its proper divisors (1).

21310229989 is an equidigital number, since it uses as much as digits as its factorization.

21310229989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 139968, while the sum is 46.

The spelling of 21310229989 in words is "twenty-one billion, three hundred ten million, two hundred twenty-nine thousand, nine hundred eighty-nine".