20747664669 has 8 divisors (see below), whose sum is σ = 29119529440. Its totient is φ = 13103788176.

The previous prime is 20747664667. The next prime is 20747664673. The reversal of 20747664669 is 96646674702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20747664669 - 2¹ = 20747664667 is a prime.

It is a super-2 number, since 2×20747664669² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (57), and also a Moran number because the ratio is a prime number: 363994117 = 20747664669 / (2 + 0 + 7 + 4 + 7 + 6 + 6 + 4 + 6 + 6 + 9).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20747664667) 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 in 7 ways as a sum of consecutive naturals, for example, 181997002 + ... + 181997115.

It is an arithmetic number, because the mean of its divisors is an integer number (3639941180).

Almost surely, 2^20747664669 is an apocalyptic number.

It is an amenable number.

20747664669 is a deficient number, since it is larger than the sum of its proper divisors (8371864771).

20747664669 is a wasteful number, since it uses less digits than its factorization.

20747664669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363994139.

The product of its (nonzero) digits is 18289152, while the sum is 57.

The spelling of 20747664669 in words is "twenty billion, seven hundred forty-seven million, six hundred sixty-four thousand, six hundred sixty-nine".