1661555146 has 16 divisors (see below), whose sum is σ = 2640059784. Its totient is φ = 781576704.

The previous prime is 1661555113. The next prime is 1661555191. The reversal of 1661555146 is 6415551661.

It can be written as a sum of positive squares in 4 ways, for example, as 1468039225 + 193515921 = 38315^2 + 13911^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1661555099 and 1661555108.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83236 + ... + 101248.

Almost surely, 2^1661555146 is an apocalyptic number.

1661555146 is a deficient number, since it is larger than the sum of its proper divisors (978504638).

1661555146 is a wasteful number, since it uses less digits than its factorization.

1661555146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20745.

The product of its digits is 108000, while the sum is 40.

The square root of 1661555146 is about 40762.1778858785. The cubic root of 1661555146 is about 1184.4177846956.

The spelling of 1661555146 in words is "one billion, six hundred sixty-one million, five hundred fifty-five thousand, one hundred forty-six".