20667725569 has 2 divisors, whose sum is σ = 20667725570. Its totient is φ = 20667725568.

The previous prime is 20667725557. The next prime is 20667725591. The reversal of 20667725569 is 96552776602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16220569600 + 4447155969 = 127360^2 + 66687^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20667725569 is a prime.

It is a super-2 number, since 2×20667725569² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20667725509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10333862784 + 10333862785.

It is an arithmetic number, because the mean of its divisors is an integer number (10333862785).

Almost surely, 2^20667725569 is an apocalyptic number.

It is an amenable number.

20667725569 is a deficient number, since it is larger than the sum of its proper divisors (1).

20667725569 is an equidigital number, since it uses as much as digits as its factorization.

20667725569 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9525600, while the sum is 55.

The spelling of 20667725569 in words is "twenty billion, six hundred sixty-seven million, seven hundred twenty-five thousand, five hundred sixty-nine".