21662329613 has 2 divisors, whose sum is σ = 21662329614. Its totient is φ = 21662329612.

The previous prime is 21662329603. The next prime is 21662329631. The reversal of 21662329613 is 31692326612.

Together with next prime (21662329631) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20961827524 + 700502089 = 144782^2 + 26467^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21662329613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21662329603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10831164806 + 10831164807.

It is an arithmetic number, because the mean of its divisors is an integer number (10831164807).

Almost surely, 2^21662329613 is an apocalyptic number.

It is an amenable number.

21662329613 is a deficient number, since it is larger than the sum of its proper divisors (1).

21662329613 is an equidigital number, since it uses as much as digits as its factorization.

21662329613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 139968, while the sum is 41.

The spelling of 21662329613 in words is "twenty-one billion, six hundred sixty-two million, three hundred twenty-nine thousand, six hundred thirteen".