20172984689 has 8 divisors (see below), whose sum is σ = 23699730432. Its totient is φ = 16928378640.

The previous prime is 20172984679. The next prime is 20172984701. The reversal of 20172984689 is 98648927102.

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

It is a cyclic number.

It is not a de Polignac number, because 20172984689 - 2¹² = 20172980593 is a prime.

It is a super-2 number, since 2×20172984689² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20172984659) 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, 70534769 + ... + 70535054.

It is an arithmetic number, because the mean of its divisors is an integer number (2962466304).

Almost surely, 2^20172984689 is an apocalyptic number.

It is an amenable number.

20172984689 is a deficient number, since it is larger than the sum of its proper divisors (3526745743).

20172984689 is a wasteful number, since it uses less digits than its factorization.

20172984689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141069847.

The product of its (nonzero) digits is 3483648, while the sum is 56.

The spelling of 20172984689 in words is "twenty billion, one hundred seventy-two million, nine hundred eighty-four thousand, six hundred eighty-nine".