1720661260531 has 16 divisors (see below), whose sum is σ = 1739342352384. Its totient is φ = 1702090285344.

The previous prime is 1720661260501. The next prime is 1720661260537. The reversal of 1720661260531 is 1350621660271.

It is a cyclic number.

It is not a de Polignac number, because 1720661260531 - 2¹³ = 1720661252339 is a prime.

It is a super-2 number, since 2×1720661260531² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1720661260537) 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 15 ways as a sum of consecutive naturals, for example, 65294500 + ... + 65320846.

It is an arithmetic number, because the mean of its divisors is an integer number (108708897024).

Almost surely, 2^{1720661260531} is an apocalyptic number.

1720661260531 is a deficient number, since it is larger than the sum of its proper divisors (18681091853).

1720661260531 is a wasteful number, since it uses less digits than its factorization.

1720661260531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28410.

The product of its (nonzero) digits is 90720, while the sum is 40.

The spelling of 1720661260531 in words is "one trillion, seven hundred twenty billion, six hundred sixty-one million, two hundred sixty thousand, five hundred thirty-one".