1689697640 has 32 divisors (see below), whose sum is σ = 3803582880. Its totient is φ = 675565632.

The previous prime is 1689697631. The next prime is 1689697651. The reversal of 1689697640 is 467969861.

It is a super-2 number, since 2×1689697640² = 5710156229243139200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90119 + ... + 107241.

It is an arithmetic number, because the mean of its divisors is an integer number (118861965).

Almost surely, 2^1689697640 is an apocalyptic number.

1689697640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1689697640 is an abundant number, since it is smaller than the sum of its proper divisors (2113885240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1689697640 is a wasteful number, since it uses less digits than its factorization.

1689697640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19601 (or 19597 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 56.

The square root of 1689697640 is about 41105.9319320217. The cubic root of 1689697640 is about 1191.0673849410.

The spelling of 1689697640 in words is "one billion, six hundred eighty-nine million, six hundred ninety-seven thousand, six hundred forty".