20317656491 has 8 divisors (see below), whose sum is σ = 22165747968. Its totient is φ = 18469737000.

The previous prime is 20317656433. The next prime is 20317656511. The reversal of 20317656491 is 19465671302.

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

It is not a de Polignac number, because 20317656491 - 2³⁴ = 3137787307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20317656431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 438986 + ... + 483056.

It is an arithmetic number, because the mean of its divisors is an integer number (2770718496).

Almost surely, 2^20317656491 is an apocalyptic number.

20317656491 is a deficient number, since it is larger than the sum of its proper divisors (1848091477).

20317656491 is a wasteful number, since it uses less digits than its factorization.

20317656491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85993.

The product of its (nonzero) digits is 272160, while the sum is 44.

The spelling of 20317656491 in words is "twenty billion, three hundred seventeen million, six hundred fifty-six thousand, four hundred ninety-one".