1720251664317 has 12 divisors (see below), whose sum is σ = 2516261225920. Its totient is φ = 1132317550728.

The previous prime is 1720251664279. The next prime is 1720251664357. The reversal of 1720251664317 is 7134661520271.

1720251664317 is a `hidden beast` number, since 1 + 7 + 20 + 251 + 6 + 64 + 317 = 666.

It is not a de Polignac number, because 1720251664317 - 2⁶ = 1720251664253 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 (1720251664357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1209740263 + ... + 1209741684.

Almost surely, 2^{1720251664317} is an apocalyptic number.

It is an amenable number.

1720251664317 is a deficient number, since it is larger than the sum of its proper divisors (796009561603).

1720251664317 is a wasteful number, since it uses less digits than its factorization.

1720251664317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2419482032 (or 2419482029 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 45.

The spelling of 1720251664317 in words is "one trillion, seven hundred twenty billion, two hundred fifty-one million, six hundred sixty-four thousand, three hundred seventeen".