1687540013 has 4 divisors (see below), whose sum is σ = 1694782908. Its totient is φ = 1680297120.

The previous prime is 1687539991. The next prime is 1687540109. The reversal of 1687540013 is 3100457861.

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 1177999684 + 509540329 = 34322^2 + 22573^2 .

It is a cyclic number.

It is not a de Polignac number, because 1687540013 - 2¹⁰ = 1687538989 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 (1687548013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3621098 + ... + 3621563.

It is an arithmetic number, because the mean of its divisors is an integer number (423695727).

Almost surely, 2^1687540013 is an apocalyptic number.

It is an amenable number.

1687540013 is a deficient number, since it is larger than the sum of its proper divisors (7242895).

1687540013 is an equidigital number, since it uses as much as digits as its factorization.

1687540013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7242894.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 1687540013 is about 41079.6788327270. The cubic root of 1687540013 is about 1190.5601987800.

Adding to 1687540013 its reverse (3100457861), we get a palindrome (4787997874).

The spelling of 1687540013 in words is "one billion, six hundred eighty-seven million, five hundred forty thousand, thirteen".