1681617601646 has 8 divisors (see below), whose sum is σ = 2546915979504. Its totient is φ = 832645608480.

The previous prime is 1681617601627. The next prime is 1681617601669. The reversal of 1681617601646 is 6461067161861.

It is a happy number.

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

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 4081595915 + ... + 4081596326.

It is an arithmetic number, because the mean of its divisors is an integer number (318364497438).

Almost surely, 2^{1681617601646} is an apocalyptic number.

1681617601646 is a deficient number, since it is larger than the sum of its proper divisors (865298377858).

1681617601646 is a wasteful number, since it uses less digits than its factorization.

1681617601646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8163192346.

The product of its (nonzero) digits is 1741824, while the sum is 53.

The spelling of 1681617601646 in words is "one trillion, six hundred eighty-one billion, six hundred seventeen million, six hundred one thousand, six hundred forty-six".