1686639429 has 24 divisors (see below), whose sum is σ = 2536646112. Its totient is φ = 1119906000.

The previous prime is 1686639419. The next prime is 1686639467. The reversal of 1686639429 is 9249366861.

It is not a de Polignac number, because 1686639429 - 2⁵ = 1686639397 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1686639419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 47167 + ... + 74819.

It is an arithmetic number, because the mean of its divisors is an integer number (105693588).

Almost surely, 2^1686639429 is an apocalyptic number.

It is an amenable number.

1686639429 is a deficient number, since it is larger than the sum of its proper divisors (850006683).

1686639429 is an equidigital number, since it uses as much as digits as its factorization.

1686639429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27919 (or 27907 counting only the distinct ones).

The product of its digits is 3359232, while the sum is 54.

The square root of 1686639429 is about 41068.7159404820. The cubic root of 1686639429 is about 1190.3483736289.

The spelling of 1686639429 in words is "one billion, six hundred eighty-six million, six hundred thirty-nine thousand, four hundred twenty-nine".