21472567709 has 2 divisors, whose sum is σ = 21472567710. Its totient is φ = 21472567708.

The previous prime is 21472567703. The next prime is 21472567729. The reversal of 21472567709 is 90776527412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20919283225 + 553284484 = 144635^2 + 23522^2 .

It is a cyclic number.

It is not a de Polignac number, because 21472567709 - 2²⁰ = 21471519133 is a prime.

It is a super-2 number, since 2×21472567709² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21472567703) 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, 10736283854 + 10736283855.

It is an arithmetic number, because the mean of its divisors is an integer number (10736283855).

Almost surely, 2^21472567709 is an apocalyptic number.

It is an amenable number.

21472567709 is a deficient number, since it is larger than the sum of its proper divisors (1).

21472567709 is an equidigital number, since it uses as much as digits as its factorization.

21472567709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1481760, while the sum is 50.

The spelling of 21472567709 in words is "twenty-one billion, four hundred seventy-two million, five hundred sixty-seven thousand, seven hundred nine".