1681609802 has 8 divisors (see below), whose sum is σ = 2547389412. Its totient is φ = 832480000.

The previous prime is 1681609777. The next prime is 1681609829. The reversal of 1681609802 is 2089061861.

It can be written as a sum of positive squares in 2 ways, for example, as 1665537721 + 16072081 = 40811^2 + 4009^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 1681609802.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4162199 + ... + 4162602.

Almost surely, 2^1681609802 is an apocalyptic number.

1681609802 is a deficient number, since it is larger than the sum of its proper divisors (865779610).

1681609802 is a wasteful number, since it uses less digits than its factorization.

1681609802 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8324904.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 1681609802 is about 41007.4359354496. The cubic root of 1681609802 is about 1189.1639732047.

The spelling of 1681609802 in words is "one billion, six hundred eighty-one million, six hundred nine thousand, eight hundred two".