1687641771247 has 8 divisors (see below), whose sum is σ = 1746560200320. Its totient is φ = 1629003240480.

The previous prime is 1687641771173. The next prime is 1687641771329. The reversal of 1687641771247 is 7421771467861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1687641771247 - 2⁷ = 1687641771119 is a prime.

It is a super-2 number, since 2×1687641771247² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1687641771047) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69962308 + ... + 69986425.

It is an arithmetic number, because the mean of its divisors is an integer number (218320025040).

Almost surely, 2^{1687641771247} is an apocalyptic number.

1687641771247 is a deficient number, since it is larger than the sum of its proper divisors (58918429073).

1687641771247 is a wasteful number, since it uses less digits than its factorization.

1687641771247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139949153.

The product of its digits is 22127616, while the sum is 61.

The spelling of 1687641771247 in words is "one trillion, six hundred eighty-seven billion, six hundred forty-one million, seven hundred seventy-one thousand, two hundred forty-seven".