1721725317 has 24 divisors (see below), whose sum is σ = 2681844984. Its totient is φ = 1058097024.

The previous prime is 1721725277. The next prime is 1721725339. The reversal of 1721725317 is 7135271271.

It is a happy number.

1721725317 is a `hidden beast` number, since 172 + 172 + 5 + 317 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 292204836 + 1429520481 = 17094^2 + 37809^2 .

It is not a de Polignac number, because 1721725317 - 2⁶ = 1721725253 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1721725387) 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 23 ways as a sum of consecutive naturals, for example, 80923 + ... + 99959.

It is an arithmetic number, because the mean of its divisors is an integer number (111743541).

Almost surely, 2^1721725317 is an apocalyptic number.

It is an amenable number.

1721725317 is a deficient number, since it is larger than the sum of its proper divisors (960119667).

1721725317 is a wasteful number, since it uses less digits than its factorization.

1721725317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19829 (or 19826 counting only the distinct ones).

The product of its digits is 20580, while the sum is 36.

The square root of 1721725317 is about 41493.6780365395. The cubic root of 1721725317 is about 1198.5457654635.

Adding to 1721725317 its reverse (7135271271), we get a palindrome (8856996588).

The spelling of 1721725317 in words is "one billion, seven hundred twenty-one million, seven hundred twenty-five thousand, three hundred seventeen".