21724111469 has 4 divisors (see below), whose sum is σ = 21732121596. Its totient is φ = 21716101344.

The previous prime is 21724111463. The next prime is 21724111523. The reversal of 21724111469 is 96411142712.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20993112100 + 730999369 = 144890^2 + 27037^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21724111469 is a prime.

It is a super-2 number, since 2×21724111469² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21724111463) 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 in 3 ways as a sum of consecutive naturals, for example, 4000994 + ... + 4006419.

It is an arithmetic number, because the mean of its divisors is an integer number (5433030399).

Almost surely, 2^21724111469 is an apocalyptic number.

It is an amenable number.

21724111469 is a deficient number, since it is larger than the sum of its proper divisors (8010127).

21724111469 is an equidigital number, since it uses as much as digits as its factorization.

21724111469 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8010126.

The product of its digits is 24192, while the sum is 38.

The spelling of 21724111469 in words is "twenty-one billion, seven hundred twenty-four million, one hundred eleven thousand, four hundred sixty-nine".