20117553664465 has 16 divisors (see below), whose sum is σ = 25084840283136. Its totient is φ = 15471735336000.

The previous prime is 20117553664451. The next prime is 20117553664519. The reversal of 20117553664465 is 56446635571102.

It is not a de Polignac number, because 20117553664465 - 2⁵ = 20117553664433 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 429747022 + ... + 429793831.

It is an arithmetic number, because the mean of its divisors is an integer number (1567802517696).

Almost surely, 2^{20117553664465} is an apocalyptic number.

It is an amenable number.

20117553664465 is a deficient number, since it is larger than the sum of its proper divisors (4967286618671).

20117553664465 is a wasteful number, since it uses less digits than its factorization.

20117553664465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 859541040.

The product of its (nonzero) digits is 18144000, while the sum is 55.

The spelling of 20117553664465 in words is "twenty trillion, one hundred seventeen billion, five hundred fifty-three million, six hundred sixty-four thousand, four hundred sixty-five".