1661803738 has 12 divisors (see below), whose sum is σ = 2899678122. Its totient is φ = 712201560.

The previous prime is 1661803729. The next prime is 1661803811. The reversal of 1661803738 is 8373081661.

It can be written as a sum of positive squares in only one way, i.e., 1019333329 + 642470409 = 31927^2 + 25347^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1661803694 and 1661803703.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8478493 + ... + 8478688.

Almost surely, 2^1661803738 is an apocalyptic number.

1661803738 is a deficient number, since it is larger than the sum of its proper divisors (1237874384).

1661803738 is a wasteful number, since it uses less digits than its factorization.

1661803738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16957197 (or 16957190 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 1661803738 is about 40765.2270691579. The cubic root of 1661803738 is about 1184.4768502651.

The spelling of 1661803738 in words is "one billion, six hundred sixty-one million, eight hundred three thousand, seven hundred thirty-eight".