20163217955 has 4 divisors (see below), whose sum is σ = 24195861552. Its totient is φ = 16130574360.

The previous prime is 20163217937. The next prime is 20163217961. The reversal of 20163217955 is 55971236102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55971236102 = 2 ⋅27985618051.

It is not a de Polignac number, because 20163217955 - 2¹⁶ = 20163152419 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2016321791 + ... + 2016321800.

It is an arithmetic number, because the mean of its divisors is an integer number (6048965388).

Almost surely, 2^20163217955 is an apocalyptic number.

20163217955 is a deficient number, since it is larger than the sum of its proper divisors (4032643597).

20163217955 is an equidigital number, since it uses as much as digits as its factorization.

20163217955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4032643596.

The product of its (nonzero) digits is 113400, while the sum is 41.

The spelling of 20163217955 in words is "twenty billion, one hundred sixty-three million, two hundred seventeen thousand, nine hundred fifty-five".