21112405669 has 2 divisors, whose sum is σ = 21112405670. Its totient is φ = 21112405668.

The previous prime is 21112405631. The next prime is 21112405747. The reversal of 21112405669 is 96650421112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11918088900 + 9194316769 = 109170^2 + 95887^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112405669 - 2¹¹ = 21112403621 is a prime.

It is a super-2 number, since 2×21112405669² (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 (21112405169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556202834 + 10556202835.

It is an arithmetic number, because the mean of its divisors is an integer number (10556202835).

Almost surely, 2^21112405669 is an apocalyptic number.

It is an amenable number.

21112405669 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112405669 is an equidigital number, since it uses as much as digits as its factorization.

21112405669 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 37.

The spelling of 21112405669 in words is "twenty-one billion, one hundred twelve million, four hundred five thousand, six hundred sixty-nine".