1688465605 has 8 divisors (see below), whose sum is σ = 2026522872. Its totient is φ = 1350529728.

The previous prime is 1688465587. The next prime is 1688465621. The reversal of 1688465605 is 5065648861.

It can be written as a sum of positive squares in 4 ways, for example, as 30835809 + 1657629796 = 5553^2 + 40714^2 .

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 1688465605 - 2¹⁷ = 1688334533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3739 + ... + 58231.

It is an arithmetic number, because the mean of its divisors is an integer number (253315359).

Almost surely, 2^1688465605 is an apocalyptic number.

It is an amenable number.

1688465605 is a deficient number, since it is larger than the sum of its proper divisors (338057267).

1688465605 is an equidigital number, since it uses as much as digits as its factorization.

1688465605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60695.

The product of its (nonzero) digits is 1382400, while the sum is 49.

The square root of 1688465605 is about 41090.9431018564. The cubic root of 1688465605 is about 1190.7778275130. Note that the first 3 decimals are identical.

The spelling of 1688465605 in words is "one billion, six hundred eighty-eight million, four hundred sixty-five thousand, six hundred five".