20261717317 has 4 divisors (see below), whose sum is σ = 20266628620. Its totient is φ = 20256806016.

The previous prime is 20261717279. The next prime is 20261717323. The reversal of 20261717317 is 71371716202.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8390743201 + 11870974116 = 91601^2 + 108954^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20261717317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20261717327) 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 3 ways as a sum of consecutive naturals, for example, 2449458 + ... + 2457715.

It is an arithmetic number, because the mean of its divisors is an integer number (5066657155).

Almost surely, 2^20261717317 is an apocalyptic number.

It is an amenable number.

20261717317 is a deficient number, since it is larger than the sum of its proper divisors (4911303).

20261717317 is an equidigital number, since it uses as much as digits as its factorization.

20261717317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4911302.

The product of its (nonzero) digits is 24696, while the sum is 37.

The spelling of 20261717317 in words is "twenty billion, two hundred sixty-one million, seven hundred seventeen thousand, three hundred seventeen".