1687648091 has 8 divisors (see below), whose sum is σ = 1765954944. Its totient is φ = 1610832960.

The previous prime is 1687648073. The next prime is 1687648121. The reversal of 1687648091 is 1908467861.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1687648091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1687648051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 370616 + ... + 375141.

It is an arithmetic number, because the mean of its divisors is an integer number (220744368).

Almost surely, 2^1687648091 is an apocalyptic number.

1687648091 is a deficient number, since it is larger than the sum of its proper divisors (78306853).

1687648091 is an equidigital number, since it uses as much as digits as its factorization.

1687648091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 745861.

The product of its (nonzero) digits is 580608, while the sum is 50.

The square root of 1687648091 is about 41080.9942795936. The cubic root of 1687648091 is about 1190.5856145958.

The spelling of 1687648091 in words is "one billion, six hundred eighty-seven million, six hundred forty-eight thousand, ninety-one".