21406989313 has 2 divisors, whose sum is σ = 21406989314. Its totient is φ = 21406989312.

The previous prime is 21406989283. The next prime is 21406989377. The reversal of 21406989313 is 31398960412.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13804370064 + 7602619249 = 117492^2 + 87193^2 .

It is a cyclic number.

It is not a de Polignac number, because 21406989313 - 2¹³ = 21406981121 is a prime.

It is not a weakly prime, because it can be changed into another prime (21406989113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10703494656 + 10703494657.

It is an arithmetic number, because the mean of its divisors is an integer number (10703494657).

Almost surely, 2^21406989313 is an apocalyptic number.

It is an amenable number.

21406989313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21406989313 is an equidigital number, since it uses as much as digits as its factorization.

21406989313 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 279936, while the sum is 46.

The spelling of 21406989313 in words is "twenty-one billion, four hundred six million, nine hundred eighty-nine thousand, three hundred thirteen".